drivers/net/wireless/iwlwifi/iwl-sta.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2003 - 2010 Intel Corporation. All rights reserved.
   4  *
   5  * Portions of this file are derived from the ipw3945 project, as well
   6  * as portions of the ieee80211 subsystem header files.
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of version 2 of the GNU General Public License as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along with
  18  * this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  20  *
  21  * The full GNU General Public License is included in this distribution in the
  22  * file called LICENSE.
  23  *
  24  * Contact Information:
  25  *  Intel Linux Wireless <ilw@linux.intel.com>
  26  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  27  *
  28  *****************************************************************************/
  29
  30 #include <net/mac80211.h>
  31 #include <linux/etherdevice.h>
  32 #include <linux/sched.h>
  33 #include <linux/lockdep.h>
  34
  35 #include "iwl-dev.h"
  36 #include "iwl-core.h"
  37 #include "iwl-sta.h"
  38
  39 /* priv->sta_lock must be held */
  40 static void iwl_sta_ucode_activate(struct iwl_priv *priv, u8 sta_id)
  41 {
  42
  43         if (!(priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE))
  44                 IWL_ERR(priv, "ACTIVATE a non DRIVER active station id %u addr %pM\n",
  45                         sta_id, priv->stations[sta_id].sta.sta.addr);
  46
  47         if (priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE) {
  48                 IWL_DEBUG_ASSOC(priv,
  49                                 "STA id %u addr %pM already present in uCode (according to driver)\n",
  50                                 sta_id, priv->stations[sta_id].sta.sta.addr);
  51         } else {
  52                 priv->stations[sta_id].used |= IWL_STA_UCODE_ACTIVE;
  53                 IWL_DEBUG_ASSOC(priv, "Added STA id %u addr %pM to uCode\n",
  54                                 sta_id, priv->stations[sta_id].sta.sta.addr);
  55         }
  56 }
  57
  58 static int iwl_process_add_sta_resp(struct iwl_priv *priv,
  59                                     struct iwl_addsta_cmd *addsta,
  60                                     struct iwl_rx_packet *pkt,
  61                                     bool sync)
  62 {
  63         u8 sta_id = addsta->sta.sta_id;
  64         unsigned long flags;
  65         int ret = -EIO;
  66
  67         if (pkt->hdr.flags & IWL_CMD_FAILED_MSK) {
  68                 IWL_ERR(priv, "Bad return from REPLY_ADD_STA (0x%08X)\n",
  69                         pkt->hdr.flags);
  70                 return ret;
  71         }
  72
  73         IWL_DEBUG_INFO(priv, "Processing response for adding station %u\n",
  74                        sta_id);
  75
  76         spin_lock_irqsave(&priv->sta_lock, flags);
  77
  78         switch (pkt->u.add_sta.status) {
  79         case ADD_STA_SUCCESS_MSK:
  80                 IWL_DEBUG_INFO(priv, "REPLY_ADD_STA PASSED\n");
  81                 iwl_sta_ucode_activate(priv, sta_id);
  82                 ret = 0;
  83                 break;
  84         case ADD_STA_NO_ROOM_IN_TABLE:
  85                 IWL_ERR(priv, "Adding station %d failed, no room in table.\n",
  86                         sta_id);
  87                 break;
  88         case ADD_STA_NO_BLOCK_ACK_RESOURCE:
  89                 IWL_ERR(priv, "Adding station %d failed, no block ack resource.\n",
  90                         sta_id);
  91                 break;
  92         case ADD_STA_MODIFY_NON_EXIST_STA:
  93                 IWL_ERR(priv, "Attempting to modify non-existing station %d\n",
  94                         sta_id);
  95                 break;
  96         default:
  97                 IWL_DEBUG_ASSOC(priv, "Received REPLY_ADD_STA:(0x%08X)\n",
  98                                 pkt->u.add_sta.status);
  99                 break;
 100         }
 101
 102         IWL_DEBUG_INFO(priv, "%s station id %u addr %pM\n",
 103                        priv->stations[sta_id].sta.mode ==
 104                        STA_CONTROL_MODIFY_MSK ?  "Modified" : "Added",
 105                        sta_id, priv->stations[sta_id].sta.sta.addr);
 106
 107         /*
 108          * XXX: The MAC address in the command buffer is often changed from
 109          * the original sent to the device. That is, the MAC address
 110          * written to the command buffer often is not the same MAC address
 111          * read from the command buffer when the command returns. This
 112          * issue has not yet been resolved and this debugging is left to
 113          * observe the problem.
 114          */
 115         IWL_DEBUG_INFO(priv, "%s station according to cmd buffer %pM\n",
 116                        priv->stations[sta_id].sta.mode ==
 117                        STA_CONTROL_MODIFY_MSK ? "Modified" : "Added",
 118                        addsta->sta.addr);
 119         spin_unlock_irqrestore(&priv->sta_lock, flags);
 120
 121         return ret;
 122 }
 123
 124 static void iwl_add_sta_callback(struct iwl_priv *priv,
 125                                  struct iwl_device_cmd *cmd,
 126                                  struct iwl_rx_packet *pkt)
 127 {
 128         struct iwl_addsta_cmd *addsta =
 129                 (struct iwl_addsta_cmd *)cmd->cmd.payload;
 130
 131         iwl_process_add_sta_resp(priv, addsta, pkt, false);
 132
 133 }
 134
 135 int iwl_send_add_sta(struct iwl_priv *priv,
 136                      struct iwl_addsta_cmd *sta, u8 flags)
 137 {
 138         struct iwl_rx_packet *pkt = NULL;
 139         int ret = 0;
 140         u8 data[sizeof(*sta)];
 141         struct iwl_host_cmd cmd = {
 142                 .id = REPLY_ADD_STA,
 143                 .flags = flags,
 144                 .data = data,
 145         };
 146         u8 sta_id __maybe_unused = sta->sta.sta_id;
 147
 148         IWL_DEBUG_INFO(priv, "Adding sta %u (%pM) %ssynchronously\n",
 149                        sta_id, sta->sta.addr, flags & CMD_ASYNC ?  "a" : "");
 150
 151         if (flags & CMD_ASYNC)
 152                 cmd.callback = iwl_add_sta_callback;
 153         else {
 154                 cmd.flags |= CMD_WANT_SKB;
 155                 might_sleep();
 156         }
 157
 158         cmd.len = priv->cfg->ops->utils->build_addsta_hcmd(sta, data);
 159         ret = iwl_send_cmd(priv, &cmd);
 160
 161         if (ret || (flags & CMD_ASYNC))
 162                 return ret;
 163
 164         if (ret == 0) {
 165                 pkt = (struct iwl_rx_packet *)cmd.reply_page;
 166                 ret = iwl_process_add_sta_resp(priv, sta, pkt, true);
 167         }
 168         iwl_free_pages(priv, cmd.reply_page);
 169
 170         return ret;
 171 }
 172 EXPORT_SYMBOL(iwl_send_add_sta);
 173
 174 static void iwl_set_ht_add_station(struct iwl_priv *priv, u8 index,
 175                                    struct ieee80211_sta *sta,
 176                                    struct iwl_rxon_context *ctx)
 177 {
 178         struct ieee80211_sta_ht_cap *sta_ht_inf = &sta->ht_cap;
 179         __le32 sta_flags;
 180         u8 mimo_ps_mode;
 181
 182         if (!sta || !sta_ht_inf->ht_supported)
 183                 goto done;
 184
 185         mimo_ps_mode = (sta_ht_inf->cap & IEEE80211_HT_CAP_SM_PS) >> 2;
 186         IWL_DEBUG_ASSOC(priv, "spatial multiplexing power save mode: %s\n",
 187                         (mimo_ps_mode == WLAN_HT_CAP_SM_PS_STATIC) ?
 188                         "static" :
 189                         (mimo_ps_mode == WLAN_HT_CAP_SM_PS_DYNAMIC) ?
 190                         "dynamic" : "disabled");
 191
 192         sta_flags = priv->stations[index].sta.station_flags;
 193
 194         sta_flags &= ~(STA_FLG_RTS_MIMO_PROT_MSK | STA_FLG_MIMO_DIS_MSK);
 195
 196         switch (mimo_ps_mode) {
 197         case WLAN_HT_CAP_SM_PS_STATIC:
 198                 sta_flags |= STA_FLG_MIMO_DIS_MSK;
 199                 break;
 200         case WLAN_HT_CAP_SM_PS_DYNAMIC:
 201                 sta_flags |= STA_FLG_RTS_MIMO_PROT_MSK;
 202                 break;
 203         case WLAN_HT_CAP_SM_PS_DISABLED:
 204                 break;
 205         default:
 206                 IWL_WARN(priv, "Invalid MIMO PS mode %d\n", mimo_ps_mode);
 207                 break;
 208         }
 209
 210         sta_flags |= cpu_to_le32(
 211               (u32)sta_ht_inf->ampdu_factor << STA_FLG_MAX_AGG_SIZE_POS);
 212
 213         sta_flags |= cpu_to_le32(
 214               (u32)sta_ht_inf->ampdu_density << STA_FLG_AGG_MPDU_DENSITY_POS);
 215
 216         if (iwl_is_ht40_tx_allowed(priv, ctx, &sta->ht_cap))
 217                 sta_flags |= STA_FLG_HT40_EN_MSK;
 218         else
 219                 sta_flags &= ~STA_FLG_HT40_EN_MSK;
 220
 221         priv->stations[index].sta.station_flags = sta_flags;
 222  done:
 223         return;
 224 }
 225
 226 /**
 227  * iwl_prep_station - Prepare station information for addition
 228  *
 229  * should be called with sta_lock held
 230  */
 231 u8 iwl_prep_station(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
 232                     const u8 *addr, bool is_ap, struct ieee80211_sta *sta)
 233 {
 234         struct iwl_station_entry *station;
 235         int i;
 236         u8 sta_id = IWL_INVALID_STATION;
 237         u16 rate;
 238
 239         if (is_ap)
 240                 sta_id = ctx->ap_sta_id;
 241         else if (is_broadcast_ether_addr(addr))
 242                 sta_id = ctx->bcast_sta_id;
 243         else
 244                 for (i = IWL_STA_ID; i < priv->hw_params.max_stations; i++) {
 245                         if (!compare_ether_addr(priv->stations[i].sta.sta.addr,
 246                                                 addr)) {
 247                                 sta_id = i;
 248                                 break;
 249                         }
 250
 251                         if (!priv->stations[i].used &&
 252                             sta_id == IWL_INVALID_STATION)
 253                                 sta_id = i;
 254                 }
 255
 256         /*
 257          * These two conditions have the same outcome, but keep them
 258          * separate
 259          */
 260         if (unlikely(sta_id == IWL_INVALID_STATION))
 261                 return sta_id;
 262
 263         /*
 264          * uCode is not able to deal with multiple requests to add a
 265          * station. Keep track if one is in progress so that we do not send
 266          * another.
 267          */
 268         if (priv->stations[sta_id].used & IWL_STA_UCODE_INPROGRESS) {
 269                 IWL_DEBUG_INFO(priv, "STA %d already in process of being added.\n",
 270                                 sta_id);
 271                 return sta_id;
 272         }
 273
 274         if ((priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE) &&
 275             (priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE) &&
 276             !compare_ether_addr(priv->stations[sta_id].sta.sta.addr, addr)) {
 277                 IWL_DEBUG_ASSOC(priv, "STA %d (%pM) already added, not adding again.\n",
 278                                 sta_id, addr);
 279                 return sta_id;
 280         }
 281
 282         station = &priv->stations[sta_id];
 283         station->used = IWL_STA_DRIVER_ACTIVE;
 284         IWL_DEBUG_ASSOC(priv, "Add STA to driver ID %d: %pM\n",
 285                         sta_id, addr);
 286         priv->num_stations++;
 287
 288         /* Set up the REPLY_ADD_STA command to send to device */
 289         memset(&station->sta, 0, sizeof(struct iwl_addsta_cmd));
 290         memcpy(station->sta.sta.addr, addr, ETH_ALEN);
 291         station->sta.mode = 0;
 292         station->sta.sta.sta_id = sta_id;
 293         station->sta.station_flags = ctx->station_flags;
 294         station->ctxid = ctx->ctxid;
 295
 296         if (sta) {
 297                 struct iwl_station_priv_common *sta_priv;
 298
 299                 sta_priv = (void *)sta->drv_priv;
 300                 sta_priv->ctx = ctx;
 301         }
 302
 303         /*
 304          * OK to call unconditionally, since local stations (IBSS BSSID
 305          * STA and broadcast STA) pass in a NULL sta, and mac80211
 306          * doesn't allow HT IBSS.
 307          */
 308         iwl_set_ht_add_station(priv, sta_id, sta, ctx);
 309
 310         /* 3945 only */
 311         rate = (priv->band == IEEE80211_BAND_5GHZ) ?
 312                 IWL_RATE_6M_PLCP : IWL_RATE_1M_PLCP;
 313         /* Turn on both antennas for the station... */
 314         station->sta.rate_n_flags = cpu_to_le16(rate | RATE_MCS_ANT_AB_MSK);
 315
 316         return sta_id;
 317
 318 }
 319 EXPORT_SYMBOL_GPL(iwl_prep_station);
 320
 321 #define STA_WAIT_TIMEOUT (HZ/2)
 322
 323 /**
 324  * iwl_add_station_common -
 325  */
 326 int iwl_add_station_common(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
 327                            const u8 *addr, bool is_ap,
 328                            struct ieee80211_sta *sta, u8 *sta_id_r)
 329 {
 330         unsigned long flags_spin;
 331         int ret = 0;
 332         u8 sta_id;
 333         struct iwl_addsta_cmd sta_cmd;
 334
 335         *sta_id_r = 0;
 336         spin_lock_irqsave(&priv->sta_lock, flags_spin);
 337         sta_id = iwl_prep_station(priv, ctx, addr, is_ap, sta);
 338         if (sta_id == IWL_INVALID_STATION) {
 339                 IWL_ERR(priv, "Unable to prepare station %pM for addition\n",
 340                         addr);
 341                 spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 342                 return -EINVAL;
 343         }
 344
 345         /*
 346          * uCode is not able to deal with multiple requests to add a
 347          * station. Keep track if one is in progress so that we do not send
 348          * another.
 349          */
 350         if (priv->stations[sta_id].used & IWL_STA_UCODE_INPROGRESS) {
 351                 IWL_DEBUG_INFO(priv, "STA %d already in process of being added.\n",
 352                                sta_id);
 353                 spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 354                 return -EEXIST;
 355         }
 356
 357         if ((priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE) &&
 358             (priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE)) {
 359                 IWL_DEBUG_ASSOC(priv, "STA %d (%pM) already added, not adding again.\n",
 360                                 sta_id, addr);
 361                 spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 362                 return -EEXIST;
 363         }
 364
 365         priv->stations[sta_id].used |= IWL_STA_UCODE_INPROGRESS;
 366         memcpy(&sta_cmd, &priv->stations[sta_id].sta, sizeof(struct iwl_addsta_cmd));
 367         spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 368
 369         /* Add station to device's station table */
 370         ret = iwl_send_add_sta(priv, &sta_cmd, CMD_SYNC);
 371         if (ret) {
 372                 spin_lock_irqsave(&priv->sta_lock, flags_spin);
 373                 IWL_ERR(priv, "Adding station %pM failed.\n",
 374                         priv->stations[sta_id].sta.sta.addr);
 375                 priv->stations[sta_id].used &= ~IWL_STA_DRIVER_ACTIVE;
 376                 priv->stations[sta_id].used &= ~IWL_STA_UCODE_INPROGRESS;
 377                 spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 378         }
 379         *sta_id_r = sta_id;
 380         return ret;
 381 }
 382 EXPORT_SYMBOL(iwl_add_station_common);
 383
 384 /**
 385  * iwl_sta_ucode_deactivate - deactivate ucode status for a station
 386  *
 387  * priv->sta_lock must be held
 388  */
 389 static void iwl_sta_ucode_deactivate(struct iwl_priv *priv, u8 sta_id)
 390 {
 391         /* Ucode must be active and driver must be non active */
 392         if ((priv->stations[sta_id].used &
 393              (IWL_STA_UCODE_ACTIVE | IWL_STA_DRIVER_ACTIVE)) != IWL_STA_UCODE_ACTIVE)
 394                 IWL_ERR(priv, "removed non active STA %u\n", sta_id);
 395
 396         priv->stations[sta_id].used &= ~IWL_STA_UCODE_ACTIVE;
 397
 398         memset(&priv->stations[sta_id], 0, sizeof(struct iwl_station_entry));
 399         IWL_DEBUG_ASSOC(priv, "Removed STA %u\n", sta_id);
 400 }
 401
 402 static int iwl_send_remove_station(struct iwl_priv *priv,
 403                                    const u8 *addr, int sta_id)
 404 {
 405         struct iwl_rx_packet *pkt;
 406         int ret;
 407
 408         unsigned long flags_spin;
 409         struct iwl_rem_sta_cmd rm_sta_cmd;
 410
 411         struct iwl_host_cmd cmd = {
 412                 .id = REPLY_REMOVE_STA,
 413                 .len = sizeof(struct iwl_rem_sta_cmd),
 414                 .flags = CMD_SYNC,
 415                 .data = &rm_sta_cmd,
 416         };
 417
 418         memset(&rm_sta_cmd, 0, sizeof(rm_sta_cmd));
 419         rm_sta_cmd.num_sta = 1;
 420         memcpy(&rm_sta_cmd.addr, addr, ETH_ALEN);
 421
 422         cmd.flags |= CMD_WANT_SKB;
 423
 424         ret = iwl_send_cmd(priv, &cmd);
 425
 426         if (ret)
 427                 return ret;
 428
 429         pkt = (struct iwl_rx_packet *)cmd.reply_page;
 430         if (pkt->hdr.flags & IWL_CMD_FAILED_MSK) {
 431                 IWL_ERR(priv, "Bad return from REPLY_REMOVE_STA (0x%08X)\n",
 432                           pkt->hdr.flags);
 433                 ret = -EIO;
 434         }
 435
 436         if (!ret) {
 437                 switch (pkt->u.rem_sta.status) {
 438                 case REM_STA_SUCCESS_MSK:
 439                         spin_lock_irqsave(&priv->sta_lock, flags_spin);
 440                         iwl_sta_ucode_deactivate(priv, sta_id);
 441                         spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 442                         IWL_DEBUG_ASSOC(priv, "REPLY_REMOVE_STA PASSED\n");
 443                         break;
 444                 default:
 445                         ret = -EIO;
 446                         IWL_ERR(priv, "REPLY_REMOVE_STA failed\n");
 447                         break;
 448                 }
 449         }
 450         iwl_free_pages(priv, cmd.reply_page);
 451
 452         return ret;
 453 }
 454
 455 /**
 456  * iwl_remove_station - Remove driver's knowledge of station.
 457  */
 458 int iwl_remove_station(struct iwl_priv *priv, const u8 sta_id,
 459                        const u8 *addr)
 460 {
 461         unsigned long flags;
 462
 463         if (!iwl_is_ready(priv)) {
 464                 IWL_DEBUG_INFO(priv,
 465                         "Unable to remove station %pM, device not ready.\n",
 466                         addr);
 467                 /*
 468                  * It is typical for stations to be removed when we are
 469                  * going down. Return success since device will be down
 470                  * soon anyway
 471                  */
 472                 return 0;
 473         }
 474
 475         IWL_DEBUG_ASSOC(priv, "Removing STA from driver:%d  %pM\n",
 476                         sta_id, addr);
 477
 478         if (WARN_ON(sta_id == IWL_INVALID_STATION))
 479                 return -EINVAL;
 480
 481         spin_lock_irqsave(&priv->sta_lock, flags);
 482
 483         if (!(priv->stations[sta_id].used & IWL_STA_DRIVER_ACTIVE)) {
 484                 IWL_DEBUG_INFO(priv, "Removing %pM but non DRIVER active\n",
 485                                 addr);
 486                 goto out_err;
 487         }
 488
 489         if (!(priv->stations[sta_id].used & IWL_STA_UCODE_ACTIVE)) {
 490                 IWL_DEBUG_INFO(priv, "Removing %pM but non UCODE active\n",
 491                                 addr);
 492                 goto out_err;
 493         }
 494
 495         if (priv->stations[sta_id].used & IWL_STA_LOCAL) {
 496                 kfree(priv->stations[sta_id].lq);
 497                 priv->stations[sta_id].lq = NULL;
 498         }
 499
 500         priv->stations[sta_id].used &= ~IWL_STA_DRIVER_ACTIVE;
 501
 502         priv->num_stations--;
 503
 504         BUG_ON(priv->num_stations < 0);
 505
 506         spin_unlock_irqrestore(&priv->sta_lock, flags);
 507
 508         return iwl_send_remove_station(priv, addr, sta_id);
 509 out_err:
 510         spin_unlock_irqrestore(&priv->sta_lock, flags);
 511         return -EINVAL;
 512 }
 513 EXPORT_SYMBOL_GPL(iwl_remove_station);
 514
 515 /**
 516  * iwl_clear_ucode_stations - clear ucode station table bits
 517  *
 518  * This function clears all the bits in the driver indicating
 519  * which stations are active in the ucode. Call when something
 520  * other than explicit station management would cause this in
 521  * the ucode, e.g. unassociated RXON.
 522  */
 523 void iwl_clear_ucode_stations(struct iwl_priv *priv,
 524                               struct iwl_rxon_context *ctx)
 525 {
 526         int i;
 527         unsigned long flags_spin;
 528         bool cleared = false;
 529
 530         IWL_DEBUG_INFO(priv, "Clearing ucode stations in driver\n");
 531
 532         spin_lock_irqsave(&priv->sta_lock, flags_spin);
 533         for (i = 0; i < priv->hw_params.max_stations; i++) {
 534                 if (ctx && ctx->ctxid != priv->stations[i].ctxid)
 535                         continue;
 536
 537                 if (priv->stations[i].used & IWL_STA_UCODE_ACTIVE) {
 538                         IWL_DEBUG_INFO(priv, "Clearing ucode active for station %d\n", i);
 539                         priv->stations[i].used &= ~IWL_STA_UCODE_ACTIVE;
 540                         cleared = true;
 541                 }
 542         }
 543         spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 544
 545         if (!cleared)
 546                 IWL_DEBUG_INFO(priv, "No active stations found to be cleared\n");
 547 }
 548 EXPORT_SYMBOL(iwl_clear_ucode_stations);
 549
 550 /**
 551  * iwl_restore_stations() - Restore driver known stations to device
 552  *
 553  * All stations considered active by driver, but not present in ucode, is
 554  * restored.
 555  *
 556  * Function sleeps.
 557  */
 558 void iwl_restore_stations(struct iwl_priv *priv, struct iwl_rxon_context *ctx)
 559 {
 560         struct iwl_addsta_cmd sta_cmd;
 561         struct iwl_link_quality_cmd lq;
 562         unsigned long flags_spin;
 563         int i;
 564         bool found = false;
 565         int ret;
 566         bool send_lq;
 567
 568         if (!iwl_is_ready(priv)) {
 569                 IWL_DEBUG_INFO(priv, "Not ready yet, not restoring any stations.\n");
 570                 return;
 571         }
 572
 573         IWL_DEBUG_ASSOC(priv, "Restoring all known stations ... start.\n");
 574         spin_lock_irqsave(&priv->sta_lock, flags_spin);
 575         for (i = 0; i < priv->hw_params.max_stations; i++) {
 576                 if (ctx->ctxid != priv->stations[i].ctxid)
 577                         continue;
 578                 if ((priv->stations[i].used & IWL_STA_DRIVER_ACTIVE) &&
 579                             !(priv->stations[i].used & IWL_STA_UCODE_ACTIVE)) {
 580                         IWL_DEBUG_ASSOC(priv, "Restoring sta %pM\n",
 581                                         priv->stations[i].sta.sta.addr);
 582                         priv->stations[i].sta.mode = 0;
 583                         priv->stations[i].used |= IWL_STA_UCODE_INPROGRESS;
 584                         found = true;
 585                 }
 586         }
 587
 588         for (i = 0; i < priv->hw_params.max_stations; i++) {
 589                 if ((priv->stations[i].used & IWL_STA_UCODE_INPROGRESS)) {
 590                         memcpy(&sta_cmd, &priv->stations[i].sta,
 591                                sizeof(struct iwl_addsta_cmd));
 592                         send_lq = false;
 593                         if (priv->stations[i].lq) {
 594                                 memcpy(&lq, priv->stations[i].lq,
 595                                        sizeof(struct iwl_link_quality_cmd));
 596                                 send_lq = true;
 597                         }
 598                         spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 599                         ret = iwl_send_add_sta(priv, &sta_cmd, CMD_SYNC);
 600                         if (ret) {
 601                                 spin_lock_irqsave(&priv->sta_lock, flags_spin);
 602                                 IWL_ERR(priv, "Adding station %pM failed.\n",
 603                                         priv->stations[i].sta.sta.addr);
 604                                 priv->stations[i].used &= ~IWL_STA_DRIVER_ACTIVE;
 605                                 priv->stations[i].used &= ~IWL_STA_UCODE_INPROGRESS;
 606                                 spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 607                         }
 608                         /*
 609                          * Rate scaling has already been initialized, send
 610                          * current LQ command
 611                          */
 612                         if (send_lq)
 613                                 iwl_send_lq_cmd(priv, ctx, &lq, CMD_SYNC, true);
 614                         spin_lock_irqsave(&priv->sta_lock, flags_spin);
 615                         priv->stations[i].used &= ~IWL_STA_UCODE_INPROGRESS;
 616                 }
 617         }
 618
 619         spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 620         if (!found)
 621                 IWL_DEBUG_INFO(priv, "Restoring all known stations .... no stations to be restored.\n");
 622         else
 623                 IWL_DEBUG_INFO(priv, "Restoring all known stations .... complete.\n");
 624 }
 625 EXPORT_SYMBOL(iwl_restore_stations);
 626
 627 int iwl_get_free_ucode_key_index(struct iwl_priv *priv)
 628 {
 629         int i;
 630
 631         for (i = 0; i < priv->sta_key_max_num; i++)
 632                 if (!test_and_set_bit(i, &priv->ucode_key_table))
 633                         return i;
 634
 635         return WEP_INVALID_OFFSET;
 636 }
 637 EXPORT_SYMBOL(iwl_get_free_ucode_key_index);
 638
 639 void iwl_dealloc_bcast_stations(struct iwl_priv *priv)
 640 {
 641         unsigned long flags;
 642         int i;
 643
 644         spin_lock_irqsave(&priv->sta_lock, flags);
 645         for (i = 0; i < priv->hw_params.max_stations; i++) {
 646                 if (!(priv->stations[i].used & IWL_STA_BCAST))
 647                         continue;
 648
 649                 priv->stations[i].used &= ~IWL_STA_UCODE_ACTIVE;
 650                 priv->num_stations--;
 651                 BUG_ON(priv->num_stations < 0);
 652                 kfree(priv->stations[i].lq);
 653                 priv->stations[i].lq = NULL;
 654         }
 655         spin_unlock_irqrestore(&priv->sta_lock, flags);
 656 }
 657 EXPORT_SYMBOL_GPL(iwl_dealloc_bcast_stations);
 658
 659 #ifdef CONFIG_IWLWIFI_DEBUG
 660 static void iwl_dump_lq_cmd(struct iwl_priv *priv,
 661                            struct iwl_link_quality_cmd *lq)
 662 {
 663         int i;
 664         IWL_DEBUG_RATE(priv, "lq station id 0x%x\n", lq->sta_id);
 665         IWL_DEBUG_RATE(priv, "lq ant 0x%X 0x%X\n",
 666                        lq->general_params.single_stream_ant_msk,
 667                        lq->general_params.dual_stream_ant_msk);
 668
 669         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
 670                 IWL_DEBUG_RATE(priv, "lq index %d 0x%X\n",
 671                                i, lq->rs_table[i].rate_n_flags);
 672 }
 673 #else
 674 static inline void iwl_dump_lq_cmd(struct iwl_priv *priv,
 675                                    struct iwl_link_quality_cmd *lq)
 676 {
 677 }
 678 #endif
 679
 680 /**
 681  * is_lq_table_valid() - Test one aspect of LQ cmd for validity
 682  *
 683  * It sometimes happens when a HT rate has been in use and we
 684  * loose connectivity with AP then mac80211 will first tell us that the
 685  * current channel is not HT anymore before removing the station. In such a
 686  * scenario the RXON flags will be updated to indicate we are not
 687  * communicating HT anymore, but the LQ command may still contain HT rates.
 688  * Test for this to prevent driver from sending LQ command between the time
 689  * RXON flags are updated and when LQ command is updated.
 690  */
 691 static bool is_lq_table_valid(struct iwl_priv *priv,
 692                               struct iwl_rxon_context *ctx,
 693                               struct iwl_link_quality_cmd *lq)
 694 {
 695         int i;
 696
 697         if (ctx->ht.enabled)
 698                 return true;
 699
 700         IWL_DEBUG_INFO(priv, "Channel %u is not an HT channel\n",
 701                        ctx->active.channel);
 702         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
 703                 if (le32_to_cpu(lq->rs_table[i].rate_n_flags) & RATE_MCS_HT_MSK) {
 704                         IWL_DEBUG_INFO(priv,
 705                                        "index %d of LQ expects HT channel\n",
 706                                        i);
 707                         return false;
 708                 }
 709         }
 710         return true;
 711 }
 712
 713 /**
 714  * iwl_send_lq_cmd() - Send link quality command
 715  * @init: This command is sent as part of station initialization right
 716  *        after station has been added.
 717  *
 718  * The link quality command is sent as the last step of station creation.
 719  * This is the special case in which init is set and we call a callback in
 720  * this case to clear the state indicating that station creation is in
 721  * progress.
 722  */
 723 int iwl_send_lq_cmd(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
 724                     struct iwl_link_quality_cmd *lq, u8 flags, bool init)
 725 {
 726         int ret = 0;
 727         unsigned long flags_spin;
 728
 729         struct iwl_host_cmd cmd = {
 730                 .id = REPLY_TX_LINK_QUALITY_CMD,
 731                 .len = sizeof(struct iwl_link_quality_cmd),
 732                 .flags = flags,
 733                 .data = lq,
 734         };
 735
 736         if (WARN_ON(lq->sta_id == IWL_INVALID_STATION))
 737                 return -EINVAL;
 738
 739         iwl_dump_lq_cmd(priv, lq);
 740         BUG_ON(init && (cmd.flags & CMD_ASYNC));
 741
 742         if (is_lq_table_valid(priv, ctx, lq))
 743                 ret = iwl_send_cmd(priv, &cmd);
 744         else
 745                 ret = -EINVAL;
 746
 747         if (cmd.flags & CMD_ASYNC)
 748                 return ret;
 749
 750         if (init) {
 751                 IWL_DEBUG_INFO(priv, "init LQ command complete, clearing sta addition status for sta %d\n",
 752                                lq->sta_id);
 753                 spin_lock_irqsave(&priv->sta_lock, flags_spin);
 754                 priv->stations[lq->sta_id].used &= ~IWL_STA_UCODE_INPROGRESS;
 755                 spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 756         }
 757         return ret;
 758 }
 759 EXPORT_SYMBOL(iwl_send_lq_cmd);
 760
 761 int iwl_mac_sta_remove(struct ieee80211_hw *hw,
 762                        struct ieee80211_vif *vif,
 763                        struct ieee80211_sta *sta)
 764 {
 765         struct iwl_priv *priv = hw->priv;
 766         struct iwl_station_priv_common *sta_common = (void *)sta->drv_priv;
 767         int ret;
 768
 769         IWL_DEBUG_INFO(priv, "received request to remove station %pM\n",
 770                         sta->addr);
 771         mutex_lock(&priv->mutex);
 772         IWL_DEBUG_INFO(priv, "proceeding to remove station %pM\n",
 773                         sta->addr);
 774         ret = iwl_remove_station(priv, sta_common->sta_id, sta->addr);
 775         if (ret)
 776                 IWL_ERR(priv, "Error removing station %pM\n",
 777                         sta->addr);
 778         mutex_unlock(&priv->mutex);
 779         return ret;
 780 }
 781 EXPORT_SYMBOL(iwl_mac_sta_remove);