drivers/net/wireless/iwlwifi/dvm/scan.c

   1 /******************************************************************************
   2  *
   3  * GPL LICENSE SUMMARY
   4  *
   5  * Copyright(c) 2008 - 2013 Intel Corporation. All rights reserved.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of version 2 of the GNU General Public License as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
  19  * USA
  20  *
  21  * The full GNU General Public License is included in this distribution
  22  * in the file called COPYING.
  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 #include <linux/slab.h>
  29 #include <linux/types.h>
  30 #include <linux/etherdevice.h>
  31 #include <net/mac80211.h>
  32
  33 #include "dev.h"
  34 #include "agn.h"
  35
  36 /* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
  37  * sending probe req.  This should be set long enough to hear probe responses
  38  * from more than one AP.  */
  39 #define IWL_ACTIVE_DWELL_TIME_24    (30)       /* all times in msec */
  40 #define IWL_ACTIVE_DWELL_TIME_52    (20)
  41
  42 #define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
  43 #define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
  44
  45 /* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
  46  * Must be set longer than active dwell time.
  47  * For the most reliable scan, set > AP beacon interval (typically 100msec). */
  48 #define IWL_PASSIVE_DWELL_TIME_24   (20)       /* all times in msec */
  49 #define IWL_PASSIVE_DWELL_TIME_52   (10)
  50 #define IWL_PASSIVE_DWELL_BASE      (100)
  51 #define IWL_CHANNEL_TUNE_TIME       5
  52 #define MAX_SCAN_CHANNEL            50
  53
  54 /* For reset radio, need minimal dwell time only */
  55 #define IWL_RADIO_RESET_DWELL_TIME      5
  56
  57 static int iwl_send_scan_abort(struct iwl_priv *priv)
  58 {
  59         int ret;
  60         struct iwl_host_cmd cmd = {
  61                 .id = REPLY_SCAN_ABORT_CMD,
  62                 .flags = CMD_SYNC | CMD_WANT_SKB,
  63         };
  64         __le32 *status;
  65
  66         /* Exit instantly with error when device is not ready
  67          * to receive scan abort command or it does not perform
  68          * hardware scan currently */
  69         if (!test_bit(STATUS_READY, &priv->status) ||
  70             !test_bit(STATUS_SCAN_HW, &priv->status) ||
  71             test_bit(STATUS_FW_ERROR, &priv->status))
  72                 return -EIO;
  73
  74         ret = iwl_dvm_send_cmd(priv, &cmd);
  75         if (ret)
  76                 return ret;
  77
  78         status = (void *)cmd.resp_pkt->data;
  79         if (*status != CAN_ABORT_STATUS) {
  80                 /* The scan abort will return 1 for success or
  81                  * 2 for "failure".  A failure condition can be
  82                  * due to simply not being in an active scan which
  83                  * can occur if we send the scan abort before we
  84                  * the microcode has notified us that a scan is
  85                  * completed. */
  86                 IWL_DEBUG_SCAN(priv, "SCAN_ABORT ret %d.\n",
  87                                le32_to_cpu(*status));
  88                 ret = -EIO;
  89         }
  90
  91         iwl_free_resp(&cmd);
  92         return ret;
  93 }
  94
  95 static void iwl_complete_scan(struct iwl_priv *priv, bool aborted)
  96 {
  97         /* check if scan was requested from mac80211 */
  98         if (priv->scan_request) {
  99                 IWL_DEBUG_SCAN(priv, "Complete scan in mac80211\n");
 100                 ieee80211_scan_completed(priv->hw, aborted);
 101         }
 102
 103         if (priv->scan_type == IWL_SCAN_ROC)
 104                 iwl_scan_roc_expired(priv);
 105
 106         priv->scan_type = IWL_SCAN_NORMAL;
 107         priv->scan_vif = NULL;
 108         priv->scan_request = NULL;
 109 }
 110
 111 static void iwl_process_scan_complete(struct iwl_priv *priv)
 112 {
 113         bool aborted;
 114
 115         lockdep_assert_held(&priv->mutex);
 116
 117         if (!test_and_clear_bit(STATUS_SCAN_COMPLETE, &priv->status))
 118                 return;
 119
 120         IWL_DEBUG_SCAN(priv, "Completed scan.\n");
 121
 122         cancel_delayed_work(&priv->scan_check);
 123
 124         aborted = test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->status);
 125         if (aborted)
 126                 IWL_DEBUG_SCAN(priv, "Aborted scan completed.\n");
 127
 128         if (!test_and_clear_bit(STATUS_SCANNING, &priv->status)) {
 129                 IWL_DEBUG_SCAN(priv, "Scan already completed.\n");
 130                 goto out_settings;
 131         }
 132
 133         if (priv->scan_type == IWL_SCAN_ROC)
 134                 iwl_scan_roc_expired(priv);
 135
 136         if (priv->scan_type != IWL_SCAN_NORMAL && !aborted) {
 137                 int err;
 138
 139                 /* Check if mac80211 requested scan during our internal scan */
 140                 if (priv->scan_request == NULL)
 141                         goto out_complete;
 142
 143                 /* If so request a new scan */
 144                 err = iwl_scan_initiate(priv, priv->scan_vif, IWL_SCAN_NORMAL,
 145                                         priv->scan_request->channels[0]->band);
 146                 if (err) {
 147                         IWL_DEBUG_SCAN(priv,
 148                                 "failed to initiate pending scan: %d\n", err);
 149                         aborted = true;
 150                         goto out_complete;
 151                 }
 152
 153                 return;
 154         }
 155
 156 out_complete:
 157         iwl_complete_scan(priv, aborted);
 158
 159 out_settings:
 160         /* Can we still talk to firmware ? */
 161         if (!iwl_is_ready_rf(priv))
 162                 return;
 163
 164         iwlagn_post_scan(priv);
 165 }
 166
 167 void iwl_force_scan_end(struct iwl_priv *priv)
 168 {
 169         lockdep_assert_held(&priv->mutex);
 170
 171         if (!test_bit(STATUS_SCANNING, &priv->status)) {
 172                 IWL_DEBUG_SCAN(priv, "Forcing scan end while not scanning\n");
 173                 return;
 174         }
 175
 176         IWL_DEBUG_SCAN(priv, "Forcing scan end\n");
 177         clear_bit(STATUS_SCANNING, &priv->status);
 178         clear_bit(STATUS_SCAN_HW, &priv->status);
 179         clear_bit(STATUS_SCAN_ABORTING, &priv->status);
 180         clear_bit(STATUS_SCAN_COMPLETE, &priv->status);
 181         iwl_complete_scan(priv, true);
 182 }
 183
 184 static void iwl_do_scan_abort(struct iwl_priv *priv)
 185 {
 186         int ret;
 187
 188         lockdep_assert_held(&priv->mutex);
 189
 190         if (!test_bit(STATUS_SCANNING, &priv->status)) {
 191                 IWL_DEBUG_SCAN(priv, "Not performing scan to abort\n");
 192                 return;
 193         }
 194
 195         if (test_and_set_bit(STATUS_SCAN_ABORTING, &priv->status)) {
 196                 IWL_DEBUG_SCAN(priv, "Scan abort in progress\n");
 197                 return;
 198         }
 199
 200         ret = iwl_send_scan_abort(priv);
 201         if (ret) {
 202                 IWL_DEBUG_SCAN(priv, "Send scan abort failed %d\n", ret);
 203                 iwl_force_scan_end(priv);
 204         } else
 205                 IWL_DEBUG_SCAN(priv, "Successfully send scan abort\n");
 206 }
 207
 208 /**
 209  * iwl_scan_cancel - Cancel any currently executing HW scan
 210  */
 211 int iwl_scan_cancel(struct iwl_priv *priv)
 212 {
 213         IWL_DEBUG_SCAN(priv, "Queuing abort scan\n");
 214         queue_work(priv->workqueue, &priv->abort_scan);
 215         return 0;
 216 }
 217
 218 /**
 219  * iwl_scan_cancel_timeout - Cancel any currently executing HW scan
 220  * @ms: amount of time to wait (in milliseconds) for scan to abort
 221  *
 222  */
 223 void iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
 224 {
 225         unsigned long timeout = jiffies + msecs_to_jiffies(ms);
 226
 227         lockdep_assert_held(&priv->mutex);
 228
 229         IWL_DEBUG_SCAN(priv, "Scan cancel timeout\n");
 230
 231         iwl_do_scan_abort(priv);
 232
 233         while (time_before_eq(jiffies, timeout)) {
 234                 if (!test_bit(STATUS_SCAN_HW, &priv->status))
 235                         goto finished;
 236                 msleep(20);
 237         }
 238
 239         return;
 240
 241  finished:
 242         /*
 243          * Now STATUS_SCAN_HW is clear. This means that the
 244          * device finished, but the background work is going
 245          * to execute at best as soon as we release the mutex.
 246          * Since we need to be able to issue a new scan right
 247          * after this function returns, run the complete here.
 248          * The STATUS_SCAN_COMPLETE bit will then be cleared
 249          * and prevent the background work from "completing"
 250          * a possible new scan.
 251          */
 252         iwl_process_scan_complete(priv);
 253 }
 254
 255 /* Service response to REPLY_SCAN_CMD (0x80) */
 256 static int iwl_rx_reply_scan(struct iwl_priv *priv,
 257                               struct iwl_rx_cmd_buffer *rxb,
 258                               struct iwl_device_cmd *cmd)
 259 {
 260 #ifdef CONFIG_IWLWIFI_DEBUG
 261         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 262         struct iwl_scanreq_notification *notif = (void *)pkt->data;
 263
 264         IWL_DEBUG_SCAN(priv, "Scan request status = 0x%x\n", notif->status);
 265 #endif
 266         return 0;
 267 }
 268
 269 /* Service SCAN_START_NOTIFICATION (0x82) */
 270 static int iwl_rx_scan_start_notif(struct iwl_priv *priv,
 271                                     struct iwl_rx_cmd_buffer *rxb,
 272                                     struct iwl_device_cmd *cmd)
 273 {
 274         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 275         struct iwl_scanstart_notification *notif = (void *)pkt->data;
 276
 277         priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
 278         IWL_DEBUG_SCAN(priv, "Scan start: "
 279                        "%d [802.11%s] "
 280                        "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
 281                        notif->channel,
 282                        notif->band ? "bg" : "a",
 283                        le32_to_cpu(notif->tsf_high),
 284                        le32_to_cpu(notif->tsf_low),
 285                        notif->status, notif->beacon_timer);
 286
 287         if (priv->scan_type == IWL_SCAN_ROC &&
 288             !priv->hw_roc_start_notified) {
 289                 ieee80211_ready_on_channel(priv->hw);
 290                 priv->hw_roc_start_notified = true;
 291         }
 292
 293         return 0;
 294 }
 295
 296 /* Service SCAN_RESULTS_NOTIFICATION (0x83) */
 297 static int iwl_rx_scan_results_notif(struct iwl_priv *priv,
 298                                       struct iwl_rx_cmd_buffer *rxb,
 299                                       struct iwl_device_cmd *cmd)
 300 {
 301 #ifdef CONFIG_IWLWIFI_DEBUG
 302         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 303         struct iwl_scanresults_notification *notif = (void *)pkt->data;
 304
 305         IWL_DEBUG_SCAN(priv, "Scan ch.res: "
 306                        "%d [802.11%s] "
 307                        "probe status: %u:%u "
 308                        "(TSF: 0x%08X:%08X) - %d "
 309                        "elapsed=%lu usec\n",
 310                        notif->channel,
 311                        notif->band ? "bg" : "a",
 312                        notif->probe_status, notif->num_probe_not_sent,
 313                        le32_to_cpu(notif->tsf_high),
 314                        le32_to_cpu(notif->tsf_low),
 315                        le32_to_cpu(notif->statistics[0]),
 316                        le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf);
 317 #endif
 318         return 0;
 319 }
 320
 321 /* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
 322 static int iwl_rx_scan_complete_notif(struct iwl_priv *priv,
 323                                        struct iwl_rx_cmd_buffer *rxb,
 324                                        struct iwl_device_cmd *cmd)
 325 {
 326         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 327         struct iwl_scancomplete_notification *scan_notif = (void *)pkt->data;
 328
 329         IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
 330                        scan_notif->scanned_channels,
 331                        scan_notif->tsf_low,
 332                        scan_notif->tsf_high, scan_notif->status);
 333
 334         IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n",
 335                        (priv->scan_band == IEEE80211_BAND_2GHZ) ? "2.4" : "5.2",
 336                        jiffies_to_msecs(jiffies - priv->scan_start));
 337
 338         /*
 339          * When aborting, we run the scan completed background work inline
 340          * and the background work must then do nothing. The SCAN_COMPLETE
 341          * bit helps implement that logic and thus needs to be set before
 342          * queueing the work. Also, since the scan abort waits for SCAN_HW
 343          * to clear, we need to set SCAN_COMPLETE before clearing SCAN_HW
 344          * to avoid a race there.
 345          */
 346         set_bit(STATUS_SCAN_COMPLETE, &priv->status);
 347         clear_bit(STATUS_SCAN_HW, &priv->status);
 348         queue_work(priv->workqueue, &priv->scan_completed);
 349
 350         if (priv->iw_mode != NL80211_IFTYPE_ADHOC &&
 351             iwl_advanced_bt_coexist(priv) &&
 352             priv->bt_status != scan_notif->bt_status) {
 353                 if (scan_notif->bt_status) {
 354                         /* BT on */
 355                         if (!priv->bt_ch_announce)
 356                                 priv->bt_traffic_load =
 357                                         IWL_BT_COEX_TRAFFIC_LOAD_HIGH;
 358                         /*
 359                          * otherwise, no traffic load information provided
 360                          * no changes made
 361                          */
 362                 } else {
 363                         /* BT off */
 364                         priv->bt_traffic_load =
 365                                 IWL_BT_COEX_TRAFFIC_LOAD_NONE;
 366                 }
 367                 priv->bt_status = scan_notif->bt_status;
 368                 queue_work(priv->workqueue,
 369                            &priv->bt_traffic_change_work);
 370         }
 371         return 0;
 372 }
 373
 374 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
 375 {
 376         /* scan handlers */
 377         priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
 378         priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
 379         priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
 380                                         iwl_rx_scan_results_notif;
 381         priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
 382                                         iwl_rx_scan_complete_notif;
 383 }
 384
 385 static u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
 386                                      enum ieee80211_band band, u8 n_probes)
 387 {
 388         if (band == IEEE80211_BAND_5GHZ)
 389                 return IWL_ACTIVE_DWELL_TIME_52 +
 390                         IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
 391         else
 392                 return IWL_ACTIVE_DWELL_TIME_24 +
 393                         IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
 394 }
 395
 396 static u16 iwl_limit_dwell(struct iwl_priv *priv, u16 dwell_time)
 397 {
 398         struct iwl_rxon_context *ctx;
 399         int limits[NUM_IWL_RXON_CTX] = {};
 400         int n_active = 0;
 401         u16 limit;
 402
 403         BUILD_BUG_ON(NUM_IWL_RXON_CTX != 2);
 404
 405         /*
 406          * If we're associated, we clamp the dwell time 98%
 407          * of the beacon interval (minus 2 * channel tune time)
 408          * If both contexts are active, we have to restrict to
 409          * 1/2 of the minimum of them, because they might be in
 410          * lock-step with the time inbetween only half of what
 411          * time we'd have in each of them.
 412          */
 413         for_each_context(priv, ctx) {
 414                 switch (ctx->staging.dev_type) {
 415                 case RXON_DEV_TYPE_P2P:
 416                         /* no timing constraints */
 417                         continue;
 418                 case RXON_DEV_TYPE_ESS:
 419                 default:
 420                         /* timing constraints if associated */
 421                         if (!iwl_is_associated_ctx(ctx))
 422                                 continue;
 423                         break;
 424                 case RXON_DEV_TYPE_CP:
 425                 case RXON_DEV_TYPE_2STA:
 426                         /*
 427                          * These seem to always have timers for TBTT
 428                          * active in uCode even when not associated yet.
 429                          */
 430                         break;
 431                 }
 432
 433                 limits[n_active++] = ctx->beacon_int ?: IWL_PASSIVE_DWELL_BASE;
 434         }
 435
 436         switch (n_active) {
 437         case 0:
 438                 return dwell_time;
 439         case 2:
 440                 limit = (limits[1] * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
 441                 limit /= 2;
 442                 dwell_time = min(limit, dwell_time);
 443                 /* fall through to limit further */
 444         case 1:
 445                 limit = (limits[0] * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
 446                 limit /= n_active;
 447                 return min(limit, dwell_time);
 448         default:
 449                 WARN_ON_ONCE(1);
 450                 return dwell_time;
 451         }
 452 }
 453
 454 static u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
 455                                       enum ieee80211_band band)
 456 {
 457         u16 passive = (band == IEEE80211_BAND_2GHZ) ?
 458             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
 459             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
 460
 461         return iwl_limit_dwell(priv, passive);
 462 }
 463
 464 /* Return valid, unused, channel for a passive scan to reset the RF */
 465 static u8 iwl_get_single_channel_number(struct iwl_priv *priv,
 466                                         enum ieee80211_band band)
 467 {
 468         struct ieee80211_supported_band *sband = priv->hw->wiphy->bands[band];
 469         struct iwl_rxon_context *ctx;
 470         int i;
 471
 472         for (i = 0; i < sband->n_channels; i++) {
 473                 bool busy = false;
 474
 475                 for_each_context(priv, ctx) {
 476                         busy = sband->channels[i].hw_value ==
 477                                 le16_to_cpu(ctx->staging.channel);
 478                         if (busy)
 479                                 break;
 480                 }
 481
 482                 if (busy)
 483                         continue;
 484
 485                 if (!(sband->channels[i].flags & IEEE80211_CHAN_DISABLED))
 486                         return sband->channels[i].hw_value;
 487         }
 488
 489         return 0;
 490 }
 491
 492 static int iwl_get_channel_for_reset_scan(struct iwl_priv *priv,
 493                                           struct ieee80211_vif *vif,
 494                                           enum ieee80211_band band,
 495                                           struct iwl_scan_channel *scan_ch)
 496 {
 497         const struct ieee80211_supported_band *sband;
 498         u16 channel;
 499
 500         sband = iwl_get_hw_mode(priv, band);
 501         if (!sband) {
 502                 IWL_ERR(priv, "invalid band\n");
 503                 return 0;
 504         }
 505
 506         channel = iwl_get_single_channel_number(priv, band);
 507         if (channel) {
 508                 scan_ch->channel = cpu_to_le16(channel);
 509                 scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 510                 scan_ch->active_dwell =
 511                         cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
 512                 scan_ch->passive_dwell =
 513                         cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
 514                 /* Set txpower levels to defaults */
 515                 scan_ch->dsp_atten = 110;
 516                 if (band == IEEE80211_BAND_5GHZ)
 517                         scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 518                 else
 519                         scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 520                 return 1;
 521         }
 522
 523         IWL_ERR(priv, "no valid channel found\n");
 524         return 0;
 525 }
 526
 527 static int iwl_get_channels_for_scan(struct iwl_priv *priv,
 528                                      struct ieee80211_vif *vif,
 529                                      enum ieee80211_band band,
 530                                      u8 is_active, u8 n_probes,
 531                                      struct iwl_scan_channel *scan_ch)
 532 {
 533         struct ieee80211_channel *chan;
 534         const struct ieee80211_supported_band *sband;
 535         u16 passive_dwell = 0;
 536         u16 active_dwell = 0;
 537         int added, i;
 538         u16 channel;
 539
 540         sband = iwl_get_hw_mode(priv, band);
 541         if (!sband)
 542                 return 0;
 543
 544         active_dwell = iwl_get_active_dwell_time(priv, band, n_probes);
 545         passive_dwell = iwl_get_passive_dwell_time(priv, band);
 546
 547         if (passive_dwell <= active_dwell)
 548                 passive_dwell = active_dwell + 1;
 549
 550         for (i = 0, added = 0; i < priv->scan_request->n_channels; i++) {
 551                 chan = priv->scan_request->channels[i];
 552
 553                 if (chan->band != band)
 554                         continue;
 555
 556                 channel = chan->hw_value;
 557                 scan_ch->channel = cpu_to_le16(channel);
 558
 559                 if (!is_active || (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN))
 560                         scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 561                 else
 562                         scan_ch->type = SCAN_CHANNEL_TYPE_ACTIVE;
 563
 564                 if (n_probes)
 565                         scan_ch->type |= IWL_SCAN_PROBE_MASK(n_probes);
 566
 567                 scan_ch->active_dwell = cpu_to_le16(active_dwell);
 568                 scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
 569
 570                 /* Set txpower levels to defaults */
 571                 scan_ch->dsp_atten = 110;
 572
 573                 /* NOTE: if we were doing 6Mb OFDM for scans we'd use
 574                  * power level:
 575                  * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
 576                  */
 577                 if (band == IEEE80211_BAND_5GHZ)
 578                         scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 579                 else
 580                         scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 581
 582                 IWL_DEBUG_SCAN(priv, "Scanning ch=%d prob=0x%X [%s %d]\n",
 583                                channel, le32_to_cpu(scan_ch->type),
 584                                (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
 585                                 "ACTIVE" : "PASSIVE",
 586                                (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
 587                                active_dwell : passive_dwell);
 588
 589                 scan_ch++;
 590                 added++;
 591         }
 592
 593         IWL_DEBUG_SCAN(priv, "total channels to scan %d\n", added);
 594         return added;
 595 }
 596
 597 /**
 598  * iwl_fill_probe_req - fill in all required fields and IE for probe request
 599  */
 600
 601 static u16 iwl_fill_probe_req(struct ieee80211_mgmt *frame, const u8 *ta,
 602                               const u8 *ies, int ie_len, const u8 *ssid,
 603                               u8 ssid_len, int left)
 604 {
 605         int len = 0;
 606         u8 *pos = NULL;
 607
 608         /* Make sure there is enough space for the probe request,
 609          * two mandatory IEs and the data */
 610         left -= 24;
 611         if (left < 0)
 612                 return 0;
 613
 614         frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
 615         eth_broadcast_addr(frame->da);
 616         memcpy(frame->sa, ta, ETH_ALEN);
 617         eth_broadcast_addr(frame->bssid);
 618         frame->seq_ctrl = 0;
 619
 620         len += 24;
 621
 622         /* ...next IE... */
 623         pos = &frame->u.probe_req.variable[0];
 624
 625         /* fill in our SSID IE */
 626         left -= ssid_len + 2;
 627         if (left < 0)
 628                 return 0;
 629         *pos++ = WLAN_EID_SSID;
 630         *pos++ = ssid_len;
 631         if (ssid && ssid_len) {
 632                 memcpy(pos, ssid, ssid_len);
 633                 pos += ssid_len;
 634         }
 635
 636         len += ssid_len + 2;
 637
 638         if (WARN_ON(left < ie_len))
 639                 return len;
 640
 641         if (ies && ie_len) {
 642                 memcpy(pos, ies, ie_len);
 643                 len += ie_len;
 644         }
 645
 646         return (u16)len;
 647 }
 648
 649 static int iwlagn_request_scan(struct iwl_priv *priv, struct ieee80211_vif *vif)
 650 {
 651         struct iwl_host_cmd cmd = {
 652                 .id = REPLY_SCAN_CMD,
 653                 .len = { sizeof(struct iwl_scan_cmd), },
 654                 .flags = CMD_SYNC,
 655         };
 656         struct iwl_scan_cmd *scan;
 657         struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
 658         u32 rate_flags = 0;
 659         u16 cmd_len = 0;
 660         u16 rx_chain = 0;
 661         enum ieee80211_band band;
 662         u8 n_probes = 0;
 663         u8 rx_ant = priv->nvm_data->valid_rx_ant;
 664         u8 rate;
 665         bool is_active = false;
 666         int  chan_mod;
 667         u8 active_chains;
 668         u8 scan_tx_antennas = priv->nvm_data->valid_tx_ant;
 669         int ret;
 670         int scan_cmd_size = sizeof(struct iwl_scan_cmd) +
 671                             MAX_SCAN_CHANNEL * sizeof(struct iwl_scan_channel) +
 672                             priv->fw->ucode_capa.max_probe_length;
 673         const u8 *ssid = NULL;
 674         u8 ssid_len = 0;
 675
 676         if (WARN_ON(priv->scan_type == IWL_SCAN_NORMAL &&
 677                     (!priv->scan_request ||
 678                      priv->scan_request->n_channels > MAX_SCAN_CHANNEL)))
 679                 return -EINVAL;
 680
 681         lockdep_assert_held(&priv->mutex);
 682
 683         if (vif)
 684                 ctx = iwl_rxon_ctx_from_vif(vif);
 685
 686         if (!priv->scan_cmd) {
 687                 priv->scan_cmd = kmalloc(scan_cmd_size, GFP_KERNEL);
 688                 if (!priv->scan_cmd) {
 689                         IWL_DEBUG_SCAN(priv,
 690                                        "fail to allocate memory for scan\n");
 691                         return -ENOMEM;
 692                 }
 693         }
 694         scan = priv->scan_cmd;
 695         memset(scan, 0, scan_cmd_size);
 696
 697         scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH;
 698         scan->quiet_time = IWL_ACTIVE_QUIET_TIME;
 699
 700         if (priv->scan_type != IWL_SCAN_ROC &&
 701             iwl_is_any_associated(priv)) {
 702                 u16 interval = 0;
 703                 u32 extra;
 704                 u32 suspend_time = 100;
 705                 u32 scan_suspend_time = 100;
 706
 707                 IWL_DEBUG_INFO(priv, "Scanning while associated...\n");
 708                 switch (priv->scan_type) {
 709                 case IWL_SCAN_ROC:
 710                         WARN_ON(1);
 711                         break;
 712                 case IWL_SCAN_RADIO_RESET:
 713                         interval = 0;
 714                         break;
 715                 case IWL_SCAN_NORMAL:
 716                         interval = vif->bss_conf.beacon_int;
 717                         break;
 718                 }
 719
 720                 scan->suspend_time = 0;
 721                 scan->max_out_time = cpu_to_le32(200 * 1024);
 722                 if (!interval)
 723                         interval = suspend_time;
 724
 725                 extra = (suspend_time / interval) << 22;
 726                 scan_suspend_time = (extra |
 727                     ((suspend_time % interval) * 1024));
 728                 scan->suspend_time = cpu_to_le32(scan_suspend_time);
 729                 IWL_DEBUG_SCAN(priv, "suspend_time 0x%X beacon interval %d\n",
 730                                scan_suspend_time, interval);
 731         } else if (priv->scan_type == IWL_SCAN_ROC) {
 732                 scan->suspend_time = 0;
 733                 scan->max_out_time = 0;
 734                 scan->quiet_time = 0;
 735                 scan->quiet_plcp_th = 0;
 736         }
 737
 738         switch (priv->scan_type) {
 739         case IWL_SCAN_RADIO_RESET:
 740                 IWL_DEBUG_SCAN(priv, "Start internal passive scan.\n");
 741                 /*
 742                  * Override quiet time as firmware checks that active
 743                  * dwell is >= quiet; since we use passive scan it'll
 744                  * not actually be used.
 745                  */
 746                 scan->quiet_time = cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
 747                 break;
 748         case IWL_SCAN_NORMAL:
 749                 if (priv->scan_request->n_ssids) {
 750                         int i, p = 0;
 751                         IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
 752                         /*
 753                          * The highest priority SSID is inserted to the
 754                          * probe request template.
 755                          */
 756                         ssid_len = priv->scan_request->ssids[0].ssid_len;
 757                         ssid = priv->scan_request->ssids[0].ssid;
 758
 759                         /*
 760                          * Invert the order of ssids, the firmware will invert
 761                          * it back.
 762                          */
 763                         for (i = priv->scan_request->n_ssids - 1; i >= 1; i--) {
 764                                 scan->direct_scan[p].id = WLAN_EID_SSID;
 765                                 scan->direct_scan[p].len =
 766                                         priv->scan_request->ssids[i].ssid_len;
 767                                 memcpy(scan->direct_scan[p].ssid,
 768                                        priv->scan_request->ssids[i].ssid,
 769                                        priv->scan_request->ssids[i].ssid_len);
 770                                 n_probes++;
 771                                 p++;
 772                         }
 773                         is_active = true;
 774                 } else
 775                         IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
 776                 break;
 777         case IWL_SCAN_ROC:
 778                 IWL_DEBUG_SCAN(priv, "Start ROC scan.\n");
 779                 break;
 780         }
 781
 782         scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
 783         scan->tx_cmd.sta_id = ctx->bcast_sta_id;
 784         scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
 785
 786         switch (priv->scan_band) {
 787         case IEEE80211_BAND_2GHZ:
 788                 scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK;
 789                 chan_mod = le32_to_cpu(
 790                         priv->contexts[IWL_RXON_CTX_BSS].active.flags &
 791                                                 RXON_FLG_CHANNEL_MODE_MSK)
 792                                        >> RXON_FLG_CHANNEL_MODE_POS;
 793                 if ((priv->scan_request && priv->scan_request->no_cck) ||
 794                     chan_mod == CHANNEL_MODE_PURE_40) {
 795                         rate = IWL_RATE_6M_PLCP;
 796                 } else {
 797                         rate = IWL_RATE_1M_PLCP;
 798                         rate_flags = RATE_MCS_CCK_MSK;
 799                 }
 800                 /*
 801                  * Internal scans are passive, so we can indiscriminately set
 802                  * the BT ignore flag on 2.4 GHz since it applies to TX only.
 803                  */
 804                 if (priv->cfg->bt_params &&
 805                     priv->cfg->bt_params->advanced_bt_coexist)
 806                         scan->tx_cmd.tx_flags |= TX_CMD_FLG_IGNORE_BT;
 807                 break;
 808         case IEEE80211_BAND_5GHZ:
 809                 rate = IWL_RATE_6M_PLCP;
 810                 break;
 811         default:
 812                 IWL_WARN(priv, "Invalid scan band\n");
 813                 return -EIO;
 814         }
 815
 816         /*
 817          * If active scanning is requested but a certain channel is
 818          * marked passive, we can do active scanning if we detect
 819          * transmissions.
 820          *
 821          * There is an issue with some firmware versions that triggers
 822          * a sysassert on a "good CRC threshold" of zero (== disabled),
 823          * on a radar channel even though this means that we should NOT
 824          * send probes.
 825          *
 826          * The "good CRC threshold" is the number of frames that we
 827          * need to receive during our dwell time on a channel before
 828          * sending out probes -- setting this to a huge value will
 829          * mean we never reach it, but at the same time work around
 830          * the aforementioned issue. Thus use IWL_GOOD_CRC_TH_NEVER
 831          * here instead of IWL_GOOD_CRC_TH_DISABLED.
 832          *
 833          * This was fixed in later versions along with some other
 834          * scan changes, and the threshold behaves as a flag in those
 835          * versions.
 836          */
 837         if (priv->new_scan_threshold_behaviour)
 838                 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
 839                                                 IWL_GOOD_CRC_TH_DISABLED;
 840         else
 841                 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
 842                                                 IWL_GOOD_CRC_TH_NEVER;
 843
 844         band = priv->scan_band;
 845
 846         if (band == IEEE80211_BAND_2GHZ &&
 847             priv->cfg->bt_params &&
 848             priv->cfg->bt_params->advanced_bt_coexist) {
 849                 /* transmit 2.4 GHz probes only on first antenna */
 850                 scan_tx_antennas = first_antenna(scan_tx_antennas);
 851         }
 852
 853         priv->scan_tx_ant[band] = iwl_toggle_tx_ant(priv,
 854                                                     priv->scan_tx_ant[band],
 855                                                     scan_tx_antennas);
 856         rate_flags |= iwl_ant_idx_to_flags(priv->scan_tx_ant[band]);
 857         scan->tx_cmd.rate_n_flags = iwl_hw_set_rate_n_flags(rate, rate_flags);
 858
 859         /*
 860          * In power save mode while associated use one chain,
 861          * otherwise use all chains
 862          */
 863         if (test_bit(STATUS_POWER_PMI, &priv->status) &&
 864             !(priv->hw->conf.flags & IEEE80211_CONF_IDLE)) {
 865                 /* rx_ant has been set to all valid chains previously */
 866                 active_chains = rx_ant &
 867                                 ((u8)(priv->chain_noise_data.active_chains));
 868                 if (!active_chains)
 869                         active_chains = rx_ant;
 870
 871                 IWL_DEBUG_SCAN(priv, "chain_noise_data.active_chains: %u\n",
 872                                 priv->chain_noise_data.active_chains);
 873
 874                 rx_ant = first_antenna(active_chains);
 875         }
 876         if (priv->cfg->bt_params &&
 877             priv->cfg->bt_params->advanced_bt_coexist &&
 878             priv->bt_full_concurrent) {
 879                 /* operated as 1x1 in full concurrency mode */
 880                 rx_ant = first_antenna(rx_ant);
 881         }
 882
 883         /* MIMO is not used here, but value is required */
 884         rx_chain |=
 885                 priv->nvm_data->valid_rx_ant << RXON_RX_CHAIN_VALID_POS;
 886         rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
 887         rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS;
 888         rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
 889         scan->rx_chain = cpu_to_le16(rx_chain);
 890         switch (priv->scan_type) {
 891         case IWL_SCAN_NORMAL:
 892                 cmd_len = iwl_fill_probe_req(
 893                                         (struct ieee80211_mgmt *)scan->data,
 894                                         vif->addr,
 895                                         priv->scan_request->ie,
 896                                         priv->scan_request->ie_len,
 897                                         ssid, ssid_len,
 898                                         scan_cmd_size - sizeof(*scan));
 899                 break;
 900         case IWL_SCAN_RADIO_RESET:
 901         case IWL_SCAN_ROC:
 902                 /* use bcast addr, will not be transmitted but must be valid */
 903                 cmd_len = iwl_fill_probe_req(
 904                                         (struct ieee80211_mgmt *)scan->data,
 905                                         iwl_bcast_addr, NULL, 0,
 906                                         NULL, 0,
 907                                         scan_cmd_size - sizeof(*scan));
 908                 break;
 909         default:
 910                 BUG();
 911         }
 912         scan->tx_cmd.len = cpu_to_le16(cmd_len);
 913
 914         scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK |
 915                                RXON_FILTER_BCON_AWARE_MSK);
 916
 917         switch (priv->scan_type) {
 918         case IWL_SCAN_RADIO_RESET:
 919                 scan->channel_count =
 920                         iwl_get_channel_for_reset_scan(priv, vif, band,
 921                                 (void *)&scan->data[cmd_len]);
 922                 break;
 923         case IWL_SCAN_NORMAL:
 924                 scan->channel_count =
 925                         iwl_get_channels_for_scan(priv, vif, band,
 926                                 is_active, n_probes,
 927                                 (void *)&scan->data[cmd_len]);
 928                 break;
 929         case IWL_SCAN_ROC: {
 930                 struct iwl_scan_channel *scan_ch;
 931                 int n_chan, i;
 932                 u16 dwell;
 933
 934                 dwell = iwl_limit_dwell(priv, priv->hw_roc_duration);
 935                 n_chan = DIV_ROUND_UP(priv->hw_roc_duration, dwell);
 936
 937                 scan->channel_count = n_chan;
 938
 939                 scan_ch = (void *)&scan->data[cmd_len];
 940
 941                 for (i = 0; i < n_chan; i++) {
 942                         scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 943                         scan_ch->channel =
 944                                 cpu_to_le16(priv->hw_roc_channel->hw_value);
 945
 946                         if (i == n_chan - 1)
 947                                 dwell = priv->hw_roc_duration - i * dwell;
 948
 949                         scan_ch->active_dwell =
 950                         scan_ch->passive_dwell = cpu_to_le16(dwell);
 951
 952                         /* Set txpower levels to defaults */
 953                         scan_ch->dsp_atten = 110;
 954
 955                         /* NOTE: if we were doing 6Mb OFDM for scans we'd use
 956                          * power level:
 957                          * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
 958                          */
 959                         if (priv->hw_roc_channel->band == IEEE80211_BAND_5GHZ)
 960                                 scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 961                         else
 962                                 scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 963
 964                         scan_ch++;
 965                 }
 966                 }
 967
 968                 break;
 969         }
 970
 971         if (scan->channel_count == 0) {
 972                 IWL_DEBUG_SCAN(priv, "channel count %d\n", scan->channel_count);
 973                 return -EIO;
 974         }
 975
 976         cmd.len[0] += le16_to_cpu(scan->tx_cmd.len) +
 977             scan->channel_count * sizeof(struct iwl_scan_channel);
 978         cmd.data[0] = scan;
 979         cmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
 980         scan->len = cpu_to_le16(cmd.len[0]);
 981
 982         /* set scan bit here for PAN params */
 983         set_bit(STATUS_SCAN_HW, &priv->status);
 984
 985         ret = iwlagn_set_pan_params(priv);
 986         if (ret) {
 987                 clear_bit(STATUS_SCAN_HW, &priv->status);
 988                 return ret;
 989         }
 990
 991         ret = iwl_dvm_send_cmd(priv, &cmd);
 992         if (ret) {
 993                 clear_bit(STATUS_SCAN_HW, &priv->status);
 994                 iwlagn_set_pan_params(priv);
 995         }
 996
 997         return ret;
 998 }
 999
1000 void iwl_init_scan_params(struct iwl_priv *priv)
1001 {
1002         u8 ant_idx = fls(priv->nvm_data->valid_tx_ant) - 1;
1003         if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ])
1004                 priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx;
1005         if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ])
1006                 priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx;
1007 }
1008
1009 int __must_check iwl_scan_initiate(struct iwl_priv *priv,
1010                                    struct ieee80211_vif *vif,
1011                                    enum iwl_scan_type scan_type,
1012                                    enum ieee80211_band band)
1013 {
1014         int ret;
1015
1016         lockdep_assert_held(&priv->mutex);
1017
1018         cancel_delayed_work(&priv->scan_check);
1019
1020         if (!iwl_is_ready_rf(priv)) {
1021                 IWL_WARN(priv, "Request scan called when driver not ready.\n");
1022                 return -EIO;
1023         }
1024
1025         if (test_bit(STATUS_SCAN_HW, &priv->status)) {
1026                 IWL_DEBUG_SCAN(priv,
1027                         "Multiple concurrent scan requests in parallel.\n");
1028                 return -EBUSY;
1029         }
1030
1031         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
1032                 IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n");
1033                 return -EBUSY;
1034         }
1035
1036         IWL_DEBUG_SCAN(priv, "Starting %sscan...\n",
1037                         scan_type == IWL_SCAN_NORMAL ? "" :
1038                         scan_type == IWL_SCAN_ROC ? "remain-on-channel " :
1039                         "internal short ");
1040
1041         set_bit(STATUS_SCANNING, &priv->status);
1042         priv->scan_type = scan_type;
1043         priv->scan_start = jiffies;
1044         priv->scan_band = band;
1045
1046         ret = iwlagn_request_scan(priv, vif);
1047         if (ret) {
1048                 clear_bit(STATUS_SCANNING, &priv->status);
1049                 priv->scan_type = IWL_SCAN_NORMAL;
1050                 return ret;
1051         }
1052
1053         queue_delayed_work(priv->workqueue, &priv->scan_check,
1054                            IWL_SCAN_CHECK_WATCHDOG);
1055
1056         return 0;
1057 }
1058
1059
1060 /*
1061  * internal short scan, this function should only been called while associated.
1062  * It will reset and tune the radio to prevent possible RF related problem
1063  */
1064 void iwl_internal_short_hw_scan(struct iwl_priv *priv)
1065 {
1066         queue_work(priv->workqueue, &priv->start_internal_scan);
1067 }
1068
1069 static void iwl_bg_start_internal_scan(struct work_struct *work)
1070 {
1071         struct iwl_priv *priv =
1072                 container_of(work, struct iwl_priv, start_internal_scan);
1073
1074         IWL_DEBUG_SCAN(priv, "Start internal scan\n");
1075
1076         mutex_lock(&priv->mutex);
1077
1078         if (priv->scan_type == IWL_SCAN_RADIO_RESET) {
1079                 IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
1080                 goto unlock;
1081         }
1082
1083         if (test_bit(STATUS_SCANNING, &priv->status)) {
1084                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
1085                 goto unlock;
1086         }
1087
1088         if (iwl_scan_initiate(priv, NULL, IWL_SCAN_RADIO_RESET, priv->band))
1089                 IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n");
1090  unlock:
1091         mutex_unlock(&priv->mutex);
1092 }
1093
1094 static void iwl_bg_scan_check(struct work_struct *data)
1095 {
1096         struct iwl_priv *priv =
1097             container_of(data, struct iwl_priv, scan_check.work);
1098
1099         IWL_DEBUG_SCAN(priv, "Scan check work\n");
1100
1101         /* Since we are here firmware does not finish scan and
1102          * most likely is in bad shape, so we don't bother to
1103          * send abort command, just force scan complete to mac80211 */
1104         mutex_lock(&priv->mutex);
1105         iwl_force_scan_end(priv);
1106         mutex_unlock(&priv->mutex);
1107 }
1108
1109 static void iwl_bg_abort_scan(struct work_struct *work)
1110 {
1111         struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
1112
1113         IWL_DEBUG_SCAN(priv, "Abort scan work\n");
1114
1115         /* We keep scan_check work queued in case when firmware will not
1116          * report back scan completed notification */
1117         mutex_lock(&priv->mutex);
1118         iwl_scan_cancel_timeout(priv, 200);
1119         mutex_unlock(&priv->mutex);
1120 }
1121
1122 static void iwl_bg_scan_completed(struct work_struct *work)
1123 {
1124         struct iwl_priv *priv =
1125                 container_of(work, struct iwl_priv, scan_completed);
1126
1127         mutex_lock(&priv->mutex);
1128         iwl_process_scan_complete(priv);
1129         mutex_unlock(&priv->mutex);
1130 }
1131
1132 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
1133 {
1134         INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
1135         INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
1136         INIT_WORK(&priv->start_internal_scan, iwl_bg_start_internal_scan);
1137         INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
1138 }
1139
1140 void iwl_cancel_scan_deferred_work(struct iwl_priv *priv)
1141 {
1142         cancel_work_sync(&priv->start_internal_scan);
1143         cancel_work_sync(&priv->abort_scan);
1144         cancel_work_sync(&priv->scan_completed);
1145
1146         if (cancel_delayed_work_sync(&priv->scan_check)) {
1147                 mutex_lock(&priv->mutex);
1148                 iwl_force_scan_end(priv);
1149                 mutex_unlock(&priv->mutex);
1150         }
1151 }
1152
1153 void iwl_scan_roc_expired(struct iwl_priv *priv)
1154 {
1155         /*
1156          * The status bit should be set here, to prevent a race
1157          * where the atomic_read returns 1, but before the execution continues
1158          * iwl_scan_offchannel_skb_status() checks if the status bit is set
1159          */
1160         set_bit(STATUS_SCAN_ROC_EXPIRED, &priv->status);
1161
1162         if (atomic_read(&priv->num_aux_in_flight) == 0) {
1163                 ieee80211_remain_on_channel_expired(priv->hw);
1164                 priv->hw_roc_channel = NULL;
1165                 schedule_delayed_work(&priv->hw_roc_disable_work,
1166                                       10 * HZ);
1167
1168                 clear_bit(STATUS_SCAN_ROC_EXPIRED, &priv->status);
1169         } else {
1170                 IWL_DEBUG_SCAN(priv, "ROC done with %d frames in aux\n",
1171                                atomic_read(&priv->num_aux_in_flight));
1172         }
1173 }
1174
1175 void iwl_scan_offchannel_skb(struct iwl_priv *priv)
1176 {
1177         WARN_ON(!priv->hw_roc_start_notified);
1178         atomic_inc(&priv->num_aux_in_flight);
1179 }
1180
1181 void iwl_scan_offchannel_skb_status(struct iwl_priv *priv)
1182 {
1183         if (atomic_dec_return(&priv->num_aux_in_flight) == 0 &&
1184             test_bit(STATUS_SCAN_ROC_EXPIRED, &priv->status)) {
1185                 IWL_DEBUG_SCAN(priv, "0 aux frames. Calling ROC expired\n");
1186                 iwl_scan_roc_expired(priv);
1187         }
1188 }