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

   1 /******************************************************************************
   2  *
   3  * GPL LICENSE SUMMARY
   4  *
   5  * Copyright(c) 2008 - 2011 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 LICENSE.GPL.
  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 "iwl-eeprom.h"
  34 #include "iwl-dev.h"
  35 #include "iwl-core.h"
  36 #include "iwl-sta.h"
  37 #include "iwl-io.h"
  38 #include "iwl-helpers.h"
  39 #include "iwl-agn.h"
  40 #include "iwl-trans.h"
  41
  42 /* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
  43  * sending probe req.  This should be set long enough to hear probe responses
  44  * from more than one AP.  */
  45 #define IWL_ACTIVE_DWELL_TIME_24    (30)       /* all times in msec */
  46 #define IWL_ACTIVE_DWELL_TIME_52    (20)
  47
  48 #define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
  49 #define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
  50
  51 /* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
  52  * Must be set longer than active dwell time.
  53  * For the most reliable scan, set > AP beacon interval (typically 100msec). */
  54 #define IWL_PASSIVE_DWELL_TIME_24   (20)       /* all times in msec */
  55 #define IWL_PASSIVE_DWELL_TIME_52   (10)
  56 #define IWL_PASSIVE_DWELL_BASE      (100)
  57 #define IWL_CHANNEL_TUNE_TIME       5
  58
  59 static int iwl_send_scan_abort(struct iwl_priv *priv)
  60 {
  61         int ret;
  62         struct iwl_rx_packet *pkt;
  63         struct iwl_host_cmd cmd = {
  64                 .id = REPLY_SCAN_ABORT_CMD,
  65                 .flags = CMD_SYNC | CMD_WANT_SKB,
  66         };
  67
  68         /* Exit instantly with error when device is not ready
  69          * to receive scan abort command or it does not perform
  70          * hardware scan currently */
  71         if (!test_bit(STATUS_READY, &priv->shrd->status) ||
  72             !test_bit(STATUS_GEO_CONFIGURED, &priv->shrd->status) ||
  73             !test_bit(STATUS_SCAN_HW, &priv->shrd->status) ||
  74             test_bit(STATUS_FW_ERROR, &priv->shrd->status) ||
  75             test_bit(STATUS_EXIT_PENDING, &priv->shrd->status))
  76                 return -EIO;
  77
  78         ret = iwl_trans_send_cmd(trans(priv), &cmd);
  79         if (ret)
  80                 return ret;
  81
  82         pkt = (struct iwl_rx_packet *)cmd.reply_page;
  83         if (pkt->u.status != CAN_ABORT_STATUS) {
  84                 /* The scan abort will return 1 for success or
  85                  * 2 for "failure".  A failure condition can be
  86                  * due to simply not being in an active scan which
  87                  * can occur if we send the scan abort before we
  88                  * the microcode has notified us that a scan is
  89                  * completed. */
  90                 IWL_DEBUG_SCAN(priv, "SCAN_ABORT ret %d.\n", pkt->u.status);
  91                 ret = -EIO;
  92         }
  93
  94         iwl_free_pages(priv->shrd, cmd.reply_page);
  95         return ret;
  96 }
  97
  98 static void iwl_complete_scan(struct iwl_priv *priv, bool aborted)
  99 {
 100         /* check if scan was requested from mac80211 */
 101         if (priv->scan_request) {
 102                 IWL_DEBUG_SCAN(priv, "Complete scan in mac80211\n");
 103                 ieee80211_scan_completed(priv->hw, aborted);
 104         }
 105
 106         if (priv->scan_type == IWL_SCAN_ROC) {
 107                 ieee80211_remain_on_channel_expired(priv->hw);
 108                 priv->hw_roc_channel = NULL;
 109                 schedule_delayed_work(&priv->hw_roc_disable_work, 10 * HZ);
 110         }
 111
 112         priv->scan_type = IWL_SCAN_NORMAL;
 113         priv->scan_vif = NULL;
 114         priv->scan_request = NULL;
 115 }
 116
 117 void iwl_force_scan_end(struct iwl_priv *priv)
 118 {
 119         lockdep_assert_held(&priv->shrd->mutex);
 120
 121         if (!test_bit(STATUS_SCANNING, &priv->shrd->status)) {
 122                 IWL_DEBUG_SCAN(priv, "Forcing scan end while not scanning\n");
 123                 return;
 124         }
 125
 126         IWL_DEBUG_SCAN(priv, "Forcing scan end\n");
 127         clear_bit(STATUS_SCANNING, &priv->shrd->status);
 128         clear_bit(STATUS_SCAN_HW, &priv->shrd->status);
 129         clear_bit(STATUS_SCAN_ABORTING, &priv->shrd->status);
 130         iwl_complete_scan(priv, true);
 131 }
 132
 133 static void iwl_do_scan_abort(struct iwl_priv *priv)
 134 {
 135         int ret;
 136
 137         lockdep_assert_held(&priv->shrd->mutex);
 138
 139         if (!test_bit(STATUS_SCANNING, &priv->shrd->status)) {
 140                 IWL_DEBUG_SCAN(priv, "Not performing scan to abort\n");
 141                 return;
 142         }
 143
 144         if (test_and_set_bit(STATUS_SCAN_ABORTING, &priv->shrd->status)) {
 145                 IWL_DEBUG_SCAN(priv, "Scan abort in progress\n");
 146                 return;
 147         }
 148
 149         ret = iwl_send_scan_abort(priv);
 150         if (ret) {
 151                 IWL_DEBUG_SCAN(priv, "Send scan abort failed %d\n", ret);
 152                 iwl_force_scan_end(priv);
 153         } else
 154                 IWL_DEBUG_SCAN(priv, "Successfully send scan abort\n");
 155 }
 156
 157 /**
 158  * iwl_scan_cancel - Cancel any currently executing HW scan
 159  */
 160 int iwl_scan_cancel(struct iwl_priv *priv)
 161 {
 162         IWL_DEBUG_SCAN(priv, "Queuing abort scan\n");
 163         queue_work(priv->shrd->workqueue, &priv->abort_scan);
 164         return 0;
 165 }
 166
 167 /**
 168  * iwl_scan_cancel_timeout - Cancel any currently executing HW scan
 169  * @ms: amount of time to wait (in milliseconds) for scan to abort
 170  *
 171  */
 172 void iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
 173 {
 174         unsigned long timeout = jiffies + msecs_to_jiffies(ms);
 175
 176         lockdep_assert_held(&priv->shrd->mutex);
 177
 178         IWL_DEBUG_SCAN(priv, "Scan cancel timeout\n");
 179
 180         iwl_do_scan_abort(priv);
 181
 182         while (time_before_eq(jiffies, timeout)) {
 183                 if (!test_bit(STATUS_SCAN_HW, &priv->shrd->status))
 184                         break;
 185                 msleep(20);
 186         }
 187 }
 188
 189 /* Service response to REPLY_SCAN_CMD (0x80) */
 190 static int iwl_rx_reply_scan(struct iwl_priv *priv,
 191                               struct iwl_rx_mem_buffer *rxb,
 192                               struct iwl_device_cmd *cmd)
 193 {
 194 #ifdef CONFIG_IWLWIFI_DEBUG
 195         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 196         struct iwl_scanreq_notification *notif =
 197             (struct iwl_scanreq_notification *)pkt->u.raw;
 198
 199         IWL_DEBUG_SCAN(priv, "Scan request status = 0x%x\n", notif->status);
 200 #endif
 201         return 0;
 202 }
 203
 204 /* Service SCAN_START_NOTIFICATION (0x82) */
 205 static int iwl_rx_scan_start_notif(struct iwl_priv *priv,
 206                                     struct iwl_rx_mem_buffer *rxb,
 207                                     struct iwl_device_cmd *cmd)
 208 {
 209         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 210         struct iwl_scanstart_notification *notif =
 211             (struct iwl_scanstart_notification *)pkt->u.raw;
 212         priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
 213         IWL_DEBUG_SCAN(priv, "Scan start: "
 214                        "%d [802.11%s] "
 215                        "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
 216                        notif->channel,
 217                        notif->band ? "bg" : "a",
 218                        le32_to_cpu(notif->tsf_high),
 219                        le32_to_cpu(notif->tsf_low),
 220                        notif->status, notif->beacon_timer);
 221
 222         if (priv->scan_type == IWL_SCAN_ROC &&
 223             !priv->hw_roc_start_notified) {
 224                 ieee80211_ready_on_channel(priv->hw);
 225                 priv->hw_roc_start_notified = true;
 226         }
 227
 228         return 0;
 229 }
 230
 231 /* Service SCAN_RESULTS_NOTIFICATION (0x83) */
 232 static int iwl_rx_scan_results_notif(struct iwl_priv *priv,
 233                                       struct iwl_rx_mem_buffer *rxb,
 234                                       struct iwl_device_cmd *cmd)
 235 {
 236 #ifdef CONFIG_IWLWIFI_DEBUG
 237         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 238         struct iwl_scanresults_notification *notif =
 239             (struct iwl_scanresults_notification *)pkt->u.raw;
 240
 241         IWL_DEBUG_SCAN(priv, "Scan ch.res: "
 242                        "%d [802.11%s] "
 243                        "probe status: %u:%u "
 244                        "(TSF: 0x%08X:%08X) - %d "
 245                        "elapsed=%lu usec\n",
 246                        notif->channel,
 247                        notif->band ? "bg" : "a",
 248                        notif->probe_status, notif->num_probe_not_sent,
 249                        le32_to_cpu(notif->tsf_high),
 250                        le32_to_cpu(notif->tsf_low),
 251                        le32_to_cpu(notif->statistics[0]),
 252                        le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf);
 253 #endif
 254         return 0;
 255 }
 256
 257 /* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
 258 static int iwl_rx_scan_complete_notif(struct iwl_priv *priv,
 259                                        struct iwl_rx_mem_buffer *rxb,
 260                                        struct iwl_device_cmd *cmd)
 261 {
 262         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 263         struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw;
 264
 265         IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
 266                        scan_notif->scanned_channels,
 267                        scan_notif->tsf_low,
 268                        scan_notif->tsf_high, scan_notif->status);
 269
 270         /* The HW is no longer scanning */
 271         clear_bit(STATUS_SCAN_HW, &priv->shrd->status);
 272
 273         IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n",
 274                        (priv->scan_band == IEEE80211_BAND_2GHZ) ? "2.4" : "5.2",
 275                        jiffies_to_msecs(jiffies - priv->scan_start));
 276
 277         queue_work(priv->shrd->workqueue, &priv->scan_completed);
 278
 279         if (priv->iw_mode != NL80211_IFTYPE_ADHOC &&
 280             iwl_advanced_bt_coexist(priv) &&
 281             priv->bt_status != scan_notif->bt_status) {
 282                 if (scan_notif->bt_status) {
 283                         /* BT on */
 284                         if (!priv->bt_ch_announce)
 285                                 priv->bt_traffic_load =
 286                                         IWL_BT_COEX_TRAFFIC_LOAD_HIGH;
 287                         /*
 288                          * otherwise, no traffic load information provided
 289                          * no changes made
 290                          */
 291                 } else {
 292                         /* BT off */
 293                         priv->bt_traffic_load =
 294                                 IWL_BT_COEX_TRAFFIC_LOAD_NONE;
 295                 }
 296                 priv->bt_status = scan_notif->bt_status;
 297                 queue_work(priv->shrd->workqueue,
 298                            &priv->bt_traffic_change_work);
 299         }
 300         return 0;
 301 }
 302
 303 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
 304 {
 305         /* scan handlers */
 306         priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
 307         priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
 308         priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
 309                                         iwl_rx_scan_results_notif;
 310         priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
 311                                         iwl_rx_scan_complete_notif;
 312 }
 313
 314 static u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
 315                                      enum ieee80211_band band, u8 n_probes)
 316 {
 317         if (band == IEEE80211_BAND_5GHZ)
 318                 return IWL_ACTIVE_DWELL_TIME_52 +
 319                         IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
 320         else
 321                 return IWL_ACTIVE_DWELL_TIME_24 +
 322                         IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
 323 }
 324
 325 static u16 iwl_limit_dwell(struct iwl_priv *priv, u16 dwell_time)
 326 {
 327         struct iwl_rxon_context *ctx;
 328
 329         /*
 330          * If we're associated, we clamp the dwell time 98%
 331          * of the smallest beacon interval (minus 2 * channel
 332          * tune time)
 333          */
 334         for_each_context(priv, ctx) {
 335                 u16 value;
 336
 337                 if (!iwl_is_associated_ctx(ctx))
 338                         continue;
 339                 value = ctx->beacon_int;
 340                 if (!value)
 341                         value = IWL_PASSIVE_DWELL_BASE;
 342                 value = (value * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
 343                 dwell_time = min(value, dwell_time);
 344         }
 345
 346         return dwell_time;
 347 }
 348
 349 static u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
 350                                       enum ieee80211_band band)
 351 {
 352         u16 passive = (band == IEEE80211_BAND_2GHZ) ?
 353             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
 354             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
 355
 356         return iwl_limit_dwell(priv, passive);
 357 }
 358
 359 static int iwl_get_single_channel_for_scan(struct iwl_priv *priv,
 360                                            struct ieee80211_vif *vif,
 361                                            enum ieee80211_band band,
 362                                            struct iwl_scan_channel *scan_ch)
 363 {
 364         const struct ieee80211_supported_band *sband;
 365         u16 passive_dwell = 0;
 366         u16 active_dwell = 0;
 367         int added = 0;
 368         u16 channel = 0;
 369
 370         sband = iwl_get_hw_mode(priv, band);
 371         if (!sband) {
 372                 IWL_ERR(priv, "invalid band\n");
 373                 return added;
 374         }
 375
 376         active_dwell = iwl_get_active_dwell_time(priv, band, 0);
 377         passive_dwell = iwl_get_passive_dwell_time(priv, band);
 378
 379         if (passive_dwell <= active_dwell)
 380                 passive_dwell = active_dwell + 1;
 381
 382         channel = iwl_get_single_channel_number(priv, band);
 383         if (channel) {
 384                 scan_ch->channel = cpu_to_le16(channel);
 385                 scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 386                 scan_ch->active_dwell = cpu_to_le16(active_dwell);
 387                 scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
 388                 /* Set txpower levels to defaults */
 389                 scan_ch->dsp_atten = 110;
 390                 if (band == IEEE80211_BAND_5GHZ)
 391                         scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 392                 else
 393                         scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 394                 added++;
 395         } else
 396                 IWL_ERR(priv, "no valid channel found\n");
 397         return added;
 398 }
 399
 400 static int iwl_get_channels_for_scan(struct iwl_priv *priv,
 401                                      struct ieee80211_vif *vif,
 402                                      enum ieee80211_band band,
 403                                      u8 is_active, u8 n_probes,
 404                                      struct iwl_scan_channel *scan_ch)
 405 {
 406         struct ieee80211_channel *chan;
 407         const struct ieee80211_supported_band *sband;
 408         const struct iwl_channel_info *ch_info;
 409         u16 passive_dwell = 0;
 410         u16 active_dwell = 0;
 411         int added, i;
 412         u16 channel;
 413
 414         sband = iwl_get_hw_mode(priv, band);
 415         if (!sband)
 416                 return 0;
 417
 418         active_dwell = iwl_get_active_dwell_time(priv, band, n_probes);
 419         passive_dwell = iwl_get_passive_dwell_time(priv, band);
 420
 421         if (passive_dwell <= active_dwell)
 422                 passive_dwell = active_dwell + 1;
 423
 424         for (i = 0, added = 0; i < priv->scan_request->n_channels; i++) {
 425                 chan = priv->scan_request->channels[i];
 426
 427                 if (chan->band != band)
 428                         continue;
 429
 430                 channel = chan->hw_value;
 431                 scan_ch->channel = cpu_to_le16(channel);
 432
 433                 ch_info = iwl_get_channel_info(priv, band, channel);
 434                 if (!is_channel_valid(ch_info)) {
 435                         IWL_DEBUG_SCAN(priv,
 436                                        "Channel %d is INVALID for this band.\n",
 437                                        channel);
 438                         continue;
 439                 }
 440
 441                 if (!is_active || is_channel_passive(ch_info) ||
 442                     (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN))
 443                         scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 444                 else
 445                         scan_ch->type = SCAN_CHANNEL_TYPE_ACTIVE;
 446
 447                 if (n_probes)
 448                         scan_ch->type |= IWL_SCAN_PROBE_MASK(n_probes);
 449
 450                 scan_ch->active_dwell = cpu_to_le16(active_dwell);
 451                 scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
 452
 453                 /* Set txpower levels to defaults */
 454                 scan_ch->dsp_atten = 110;
 455
 456                 /* NOTE: if we were doing 6Mb OFDM for scans we'd use
 457                  * power level:
 458                  * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
 459                  */
 460                 if (band == IEEE80211_BAND_5GHZ)
 461                         scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 462                 else
 463                         scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 464
 465                 IWL_DEBUG_SCAN(priv, "Scanning ch=%d prob=0x%X [%s %d]\n",
 466                                channel, le32_to_cpu(scan_ch->type),
 467                                (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
 468                                 "ACTIVE" : "PASSIVE",
 469                                (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
 470                                active_dwell : passive_dwell);
 471
 472                 scan_ch++;
 473                 added++;
 474         }
 475
 476         IWL_DEBUG_SCAN(priv, "total channels to scan %d\n", added);
 477         return added;
 478 }
 479
 480 static int iwlagn_request_scan(struct iwl_priv *priv, struct ieee80211_vif *vif)
 481 {
 482         struct iwl_host_cmd cmd = {
 483                 .id = REPLY_SCAN_CMD,
 484                 .len = { sizeof(struct iwl_scan_cmd), },
 485                 .flags = CMD_SYNC,
 486         };
 487         struct iwl_scan_cmd *scan;
 488         struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
 489         u32 rate_flags = 0;
 490         u16 cmd_len;
 491         u16 rx_chain = 0;
 492         enum ieee80211_band band;
 493         u8 n_probes = 0;
 494         u8 rx_ant = hw_params(priv).valid_rx_ant;
 495         u8 rate;
 496         bool is_active = false;
 497         int  chan_mod;
 498         u8 active_chains;
 499         u8 scan_tx_antennas = hw_params(priv).valid_tx_ant;
 500         int ret;
 501
 502         lockdep_assert_held(&priv->shrd->mutex);
 503
 504         if (vif)
 505                 ctx = iwl_rxon_ctx_from_vif(vif);
 506
 507         if (!priv->scan_cmd) {
 508                 priv->scan_cmd = kmalloc(sizeof(struct iwl_scan_cmd) +
 509                                          IWL_MAX_SCAN_SIZE, GFP_KERNEL);
 510                 if (!priv->scan_cmd) {
 511                         IWL_DEBUG_SCAN(priv,
 512                                        "fail to allocate memory for scan\n");
 513                         return -ENOMEM;
 514                 }
 515         }
 516         scan = priv->scan_cmd;
 517         memset(scan, 0, sizeof(struct iwl_scan_cmd) + IWL_MAX_SCAN_SIZE);
 518
 519         scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH;
 520         scan->quiet_time = IWL_ACTIVE_QUIET_TIME;
 521
 522         if (priv->scan_type != IWL_SCAN_ROC &&
 523             iwl_is_any_associated(priv)) {
 524                 u16 interval = 0;
 525                 u32 extra;
 526                 u32 suspend_time = 100;
 527                 u32 scan_suspend_time = 100;
 528
 529                 IWL_DEBUG_INFO(priv, "Scanning while associated...\n");
 530                 switch (priv->scan_type) {
 531                 case IWL_SCAN_ROC:
 532                         WARN_ON(1);
 533                         break;
 534                 case IWL_SCAN_RADIO_RESET:
 535                         interval = 0;
 536                         break;
 537                 case IWL_SCAN_NORMAL:
 538                         interval = vif->bss_conf.beacon_int;
 539                         break;
 540                 }
 541
 542                 scan->suspend_time = 0;
 543                 scan->max_out_time = cpu_to_le32(200 * 1024);
 544                 if (!interval)
 545                         interval = suspend_time;
 546
 547                 extra = (suspend_time / interval) << 22;
 548                 scan_suspend_time = (extra |
 549                     ((suspend_time % interval) * 1024));
 550                 scan->suspend_time = cpu_to_le32(scan_suspend_time);
 551                 IWL_DEBUG_SCAN(priv, "suspend_time 0x%X beacon interval %d\n",
 552                                scan_suspend_time, interval);
 553         } else if (priv->scan_type == IWL_SCAN_ROC) {
 554                 scan->suspend_time = 0;
 555                 scan->max_out_time = 0;
 556                 scan->quiet_time = 0;
 557                 scan->quiet_plcp_th = 0;
 558         }
 559
 560         switch (priv->scan_type) {
 561         case IWL_SCAN_RADIO_RESET:
 562                 IWL_DEBUG_SCAN(priv, "Start internal passive scan.\n");
 563                 break;
 564         case IWL_SCAN_NORMAL:
 565                 if (priv->scan_request->n_ssids) {
 566                         int i, p = 0;
 567                         IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
 568                         for (i = 0; i < priv->scan_request->n_ssids; i++) {
 569                                 /* always does wildcard anyway */
 570                                 if (!priv->scan_request->ssids[i].ssid_len)
 571                                         continue;
 572                                 scan->direct_scan[p].id = WLAN_EID_SSID;
 573                                 scan->direct_scan[p].len =
 574                                         priv->scan_request->ssids[i].ssid_len;
 575                                 memcpy(scan->direct_scan[p].ssid,
 576                                        priv->scan_request->ssids[i].ssid,
 577                                        priv->scan_request->ssids[i].ssid_len);
 578                                 n_probes++;
 579                                 p++;
 580                         }
 581                         is_active = true;
 582                 } else
 583                         IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
 584                 break;
 585         case IWL_SCAN_ROC:
 586                 IWL_DEBUG_SCAN(priv, "Start ROC scan.\n");
 587                 break;
 588         }
 589
 590         scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
 591         scan->tx_cmd.sta_id = ctx->bcast_sta_id;
 592         scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
 593
 594         switch (priv->scan_band) {
 595         case IEEE80211_BAND_2GHZ:
 596                 scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK;
 597                 chan_mod = le32_to_cpu(
 598                         priv->contexts[IWL_RXON_CTX_BSS].active.flags &
 599                                                 RXON_FLG_CHANNEL_MODE_MSK)
 600                                        >> RXON_FLG_CHANNEL_MODE_POS;
 601                 if (chan_mod == CHANNEL_MODE_PURE_40) {
 602                         rate = IWL_RATE_6M_PLCP;
 603                 } else {
 604                         rate = IWL_RATE_1M_PLCP;
 605                         rate_flags = RATE_MCS_CCK_MSK;
 606                 }
 607                 /*
 608                  * Internal scans are passive, so we can indiscriminately set
 609                  * the BT ignore flag on 2.4 GHz since it applies to TX only.
 610                  */
 611                 if (priv->cfg->bt_params &&
 612                     priv->cfg->bt_params->advanced_bt_coexist)
 613                         scan->tx_cmd.tx_flags |= TX_CMD_FLG_IGNORE_BT;
 614                 break;
 615         case IEEE80211_BAND_5GHZ:
 616                 rate = IWL_RATE_6M_PLCP;
 617                 break;
 618         default:
 619                 IWL_WARN(priv, "Invalid scan band\n");
 620                 return -EIO;
 621         }
 622
 623         /*
 624          * If active scanning is requested but a certain channel is
 625          * marked passive, we can do active scanning if we detect
 626          * transmissions.
 627          *
 628          * There is an issue with some firmware versions that triggers
 629          * a sysassert on a "good CRC threshold" of zero (== disabled),
 630          * on a radar channel even though this means that we should NOT
 631          * send probes.
 632          *
 633          * The "good CRC threshold" is the number of frames that we
 634          * need to receive during our dwell time on a channel before
 635          * sending out probes -- setting this to a huge value will
 636          * mean we never reach it, but at the same time work around
 637          * the aforementioned issue. Thus use IWL_GOOD_CRC_TH_NEVER
 638          * here instead of IWL_GOOD_CRC_TH_DISABLED.
 639          *
 640          * This was fixed in later versions along with some other
 641          * scan changes, and the threshold behaves as a flag in those
 642          * versions.
 643          */
 644         if (priv->new_scan_threshold_behaviour)
 645                 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
 646                                                 IWL_GOOD_CRC_TH_DISABLED;
 647         else
 648                 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
 649                                                 IWL_GOOD_CRC_TH_NEVER;
 650
 651         band = priv->scan_band;
 652
 653         if (priv->cfg->scan_rx_antennas[band])
 654                 rx_ant = priv->cfg->scan_rx_antennas[band];
 655
 656         if (band == IEEE80211_BAND_2GHZ &&
 657             priv->cfg->bt_params &&
 658             priv->cfg->bt_params->advanced_bt_coexist) {
 659                 /* transmit 2.4 GHz probes only on first antenna */
 660                 scan_tx_antennas = first_antenna(scan_tx_antennas);
 661         }
 662
 663         priv->scan_tx_ant[band] = iwl_toggle_tx_ant(priv,
 664                                                     priv->scan_tx_ant[band],
 665                                                     scan_tx_antennas);
 666         rate_flags |= iwl_ant_idx_to_flags(priv->scan_tx_ant[band]);
 667         scan->tx_cmd.rate_n_flags = iwl_hw_set_rate_n_flags(rate, rate_flags);
 668
 669         /* In power save mode use one chain, otherwise use all chains */
 670         if (test_bit(STATUS_POWER_PMI, &priv->shrd->status)) {
 671                 /* rx_ant has been set to all valid chains previously */
 672                 active_chains = rx_ant &
 673                                 ((u8)(priv->chain_noise_data.active_chains));
 674                 if (!active_chains)
 675                         active_chains = rx_ant;
 676
 677                 IWL_DEBUG_SCAN(priv, "chain_noise_data.active_chains: %u\n",
 678                                 priv->chain_noise_data.active_chains);
 679
 680                 rx_ant = first_antenna(active_chains);
 681         }
 682         if (priv->cfg->bt_params &&
 683             priv->cfg->bt_params->advanced_bt_coexist &&
 684             priv->bt_full_concurrent) {
 685                 /* operated as 1x1 in full concurrency mode */
 686                 rx_ant = first_antenna(rx_ant);
 687         }
 688
 689         /* MIMO is not used here, but value is required */
 690         rx_chain |=
 691                 hw_params(priv).valid_rx_ant << RXON_RX_CHAIN_VALID_POS;
 692         rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
 693         rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS;
 694         rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
 695         scan->rx_chain = cpu_to_le16(rx_chain);
 696         switch (priv->scan_type) {
 697         case IWL_SCAN_NORMAL:
 698                 cmd_len = iwl_fill_probe_req(priv,
 699                                         (struct ieee80211_mgmt *)scan->data,
 700                                         vif->addr,
 701                                         priv->scan_request->ie,
 702                                         priv->scan_request->ie_len,
 703                                         IWL_MAX_SCAN_SIZE - sizeof(*scan));
 704                 break;
 705         case IWL_SCAN_RADIO_RESET:
 706         case IWL_SCAN_ROC:
 707                 /* use bcast addr, will not be transmitted but must be valid */
 708                 cmd_len = iwl_fill_probe_req(priv,
 709                                         (struct ieee80211_mgmt *)scan->data,
 710                                         iwl_bcast_addr, NULL, 0,
 711                                         IWL_MAX_SCAN_SIZE - sizeof(*scan));
 712                 break;
 713         default:
 714                 BUG();
 715         }
 716         scan->tx_cmd.len = cpu_to_le16(cmd_len);
 717
 718         scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK |
 719                                RXON_FILTER_BCON_AWARE_MSK);
 720
 721         switch (priv->scan_type) {
 722         case IWL_SCAN_RADIO_RESET:
 723                 scan->channel_count =
 724                         iwl_get_single_channel_for_scan(priv, vif, band,
 725                                 (void *)&scan->data[cmd_len]);
 726                 break;
 727         case IWL_SCAN_NORMAL:
 728                 scan->channel_count =
 729                         iwl_get_channels_for_scan(priv, vif, band,
 730                                 is_active, n_probes,
 731                                 (void *)&scan->data[cmd_len]);
 732                 break;
 733         case IWL_SCAN_ROC: {
 734                 struct iwl_scan_channel *scan_ch;
 735                 int n_chan, i;
 736                 u16 dwell;
 737
 738                 dwell = iwl_limit_dwell(priv, priv->hw_roc_duration);
 739                 n_chan = DIV_ROUND_UP(priv->hw_roc_duration, dwell);
 740
 741                 scan->channel_count = n_chan;
 742
 743                 scan_ch = (void *)&scan->data[cmd_len];
 744
 745                 for (i = 0; i < n_chan; i++) {
 746                         scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 747                         scan_ch->channel =
 748                                 cpu_to_le16(priv->hw_roc_channel->hw_value);
 749
 750                         if (i == n_chan - 1)
 751                                 dwell = priv->hw_roc_duration - i * dwell;
 752
 753                         scan_ch->active_dwell =
 754                         scan_ch->passive_dwell = cpu_to_le16(dwell);
 755
 756                         /* Set txpower levels to defaults */
 757                         scan_ch->dsp_atten = 110;
 758
 759                         /* NOTE: if we were doing 6Mb OFDM for scans we'd use
 760                          * power level:
 761                          * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
 762                          */
 763                         if (priv->hw_roc_channel->band == IEEE80211_BAND_5GHZ)
 764                                 scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 765                         else
 766                                 scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 767
 768                         scan_ch++;
 769                 }
 770                 }
 771
 772                 break;
 773         }
 774
 775         if (scan->channel_count == 0) {
 776                 IWL_DEBUG_SCAN(priv, "channel count %d\n", scan->channel_count);
 777                 return -EIO;
 778         }
 779
 780         cmd.len[0] += le16_to_cpu(scan->tx_cmd.len) +
 781             scan->channel_count * sizeof(struct iwl_scan_channel);
 782         cmd.data[0] = scan;
 783         cmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
 784         scan->len = cpu_to_le16(cmd.len[0]);
 785
 786         /* set scan bit here for PAN params */
 787         set_bit(STATUS_SCAN_HW, &priv->shrd->status);
 788
 789         ret = iwlagn_set_pan_params(priv);
 790         if (ret)
 791                 return ret;
 792
 793         ret = iwl_trans_send_cmd(trans(priv), &cmd);
 794         if (ret) {
 795                 clear_bit(STATUS_SCAN_HW, &priv->shrd->status);
 796                 iwlagn_set_pan_params(priv);
 797         }
 798
 799         return ret;
 800 }
 801
 802 void iwl_init_scan_params(struct iwl_priv *priv)
 803 {
 804         u8 ant_idx = fls(hw_params(priv).valid_tx_ant) - 1;
 805         if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ])
 806                 priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx;
 807         if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ])
 808                 priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx;
 809 }
 810
 811 int __must_check iwl_scan_initiate(struct iwl_priv *priv,
 812                                    struct ieee80211_vif *vif,
 813                                    enum iwl_scan_type scan_type,
 814                                    enum ieee80211_band band)
 815 {
 816         int ret;
 817
 818         lockdep_assert_held(&priv->shrd->mutex);
 819
 820         cancel_delayed_work(&priv->scan_check);
 821
 822         if (!iwl_is_ready_rf(priv->shrd)) {
 823                 IWL_WARN(priv, "Request scan called when driver not ready.\n");
 824                 return -EIO;
 825         }
 826
 827         if (test_bit(STATUS_SCAN_HW, &priv->shrd->status)) {
 828                 IWL_DEBUG_SCAN(priv,
 829                         "Multiple concurrent scan requests in parallel.\n");
 830                 return -EBUSY;
 831         }
 832
 833         if (test_bit(STATUS_SCAN_ABORTING, &priv->shrd->status)) {
 834                 IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n");
 835                 return -EBUSY;
 836         }
 837
 838         IWL_DEBUG_SCAN(priv, "Starting %sscan...\n",
 839                         scan_type == IWL_SCAN_NORMAL ? "" :
 840                         scan_type == IWL_SCAN_ROC ? "remain-on-channel " :
 841                         "internal short ");
 842
 843         set_bit(STATUS_SCANNING, &priv->shrd->status);
 844         priv->scan_type = scan_type;
 845         priv->scan_start = jiffies;
 846         priv->scan_band = band;
 847
 848         ret = iwlagn_request_scan(priv, vif);
 849         if (ret) {
 850                 clear_bit(STATUS_SCANNING, &priv->shrd->status);
 851                 priv->scan_type = IWL_SCAN_NORMAL;
 852                 return ret;
 853         }
 854
 855         queue_delayed_work(priv->shrd->workqueue, &priv->scan_check,
 856                            IWL_SCAN_CHECK_WATCHDOG);
 857
 858         return 0;
 859 }
 860
 861 int iwl_mac_hw_scan(struct ieee80211_hw *hw,
 862                     struct ieee80211_vif *vif,
 863                     struct cfg80211_scan_request *req)
 864 {
 865         struct iwl_priv *priv = hw->priv;
 866         int ret;
 867
 868         IWL_DEBUG_MAC80211(priv, "enter\n");
 869
 870         if (req->n_channels == 0)
 871                 return -EINVAL;
 872
 873         mutex_lock(&priv->shrd->mutex);
 874
 875         /*
 876          * If an internal scan is in progress, just set
 877          * up the scan_request as per above.
 878          */
 879         if (priv->scan_type != IWL_SCAN_NORMAL) {
 880                 IWL_DEBUG_SCAN(priv,
 881                                "SCAN request during internal scan - defer\n");
 882                 priv->scan_request = req;
 883                 priv->scan_vif = vif;
 884                 ret = 0;
 885         } else {
 886                 priv->scan_request = req;
 887                 priv->scan_vif = vif;
 888                 /*
 889                  * mac80211 will only ask for one band at a time
 890                  * so using channels[0] here is ok
 891                  */
 892                 ret = iwl_scan_initiate(priv, vif, IWL_SCAN_NORMAL,
 893                                         req->channels[0]->band);
 894                 if (ret) {
 895                         priv->scan_request = NULL;
 896                         priv->scan_vif = NULL;
 897                 }
 898         }
 899
 900         IWL_DEBUG_MAC80211(priv, "leave\n");
 901
 902         mutex_unlock(&priv->shrd->mutex);
 903
 904         return ret;
 905 }
 906
 907 /*
 908  * internal short scan, this function should only been called while associated.
 909  * It will reset and tune the radio to prevent possible RF related problem
 910  */
 911 void iwl_internal_short_hw_scan(struct iwl_priv *priv)
 912 {
 913         queue_work(priv->shrd->workqueue, &priv->start_internal_scan);
 914 }
 915
 916 static void iwl_bg_start_internal_scan(struct work_struct *work)
 917 {
 918         struct iwl_priv *priv =
 919                 container_of(work, struct iwl_priv, start_internal_scan);
 920
 921         IWL_DEBUG_SCAN(priv, "Start internal scan\n");
 922
 923         mutex_lock(&priv->shrd->mutex);
 924
 925         if (priv->scan_type == IWL_SCAN_RADIO_RESET) {
 926                 IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
 927                 goto unlock;
 928         }
 929
 930         if (test_bit(STATUS_SCANNING, &priv->shrd->status)) {
 931                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
 932                 goto unlock;
 933         }
 934
 935         if (iwl_scan_initiate(priv, NULL, IWL_SCAN_RADIO_RESET, priv->band))
 936                 IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n");
 937  unlock:
 938         mutex_unlock(&priv->shrd->mutex);
 939 }
 940
 941 static void iwl_bg_scan_check(struct work_struct *data)
 942 {
 943         struct iwl_priv *priv =
 944             container_of(data, struct iwl_priv, scan_check.work);
 945
 946         IWL_DEBUG_SCAN(priv, "Scan check work\n");
 947
 948         /* Since we are here firmware does not finish scan and
 949          * most likely is in bad shape, so we don't bother to
 950          * send abort command, just force scan complete to mac80211 */
 951         mutex_lock(&priv->shrd->mutex);
 952         iwl_force_scan_end(priv);
 953         mutex_unlock(&priv->shrd->mutex);
 954 }
 955
 956 /**
 957  * iwl_fill_probe_req - fill in all required fields and IE for probe request
 958  */
 959
 960 u16 iwl_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
 961                        const u8 *ta, const u8 *ies, int ie_len, int left)
 962 {
 963         int len = 0;
 964         u8 *pos = NULL;
 965
 966         /* Make sure there is enough space for the probe request,
 967          * two mandatory IEs and the data */
 968         left -= 24;
 969         if (left < 0)
 970                 return 0;
 971
 972         frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
 973         memcpy(frame->da, iwl_bcast_addr, ETH_ALEN);
 974         memcpy(frame->sa, ta, ETH_ALEN);
 975         memcpy(frame->bssid, iwl_bcast_addr, ETH_ALEN);
 976         frame->seq_ctrl = 0;
 977
 978         len += 24;
 979
 980         /* ...next IE... */
 981         pos = &frame->u.probe_req.variable[0];
 982
 983         /* fill in our indirect SSID IE */
 984         left -= 2;
 985         if (left < 0)
 986                 return 0;
 987         *pos++ = WLAN_EID_SSID;
 988         *pos++ = 0;
 989
 990         len += 2;
 991
 992         if (WARN_ON(left < ie_len))
 993                 return len;
 994
 995         if (ies && ie_len) {
 996                 memcpy(pos, ies, ie_len);
 997                 len += ie_len;
 998         }
 999
1000         return (u16)len;
1001 }
1002
1003 static void iwl_bg_abort_scan(struct work_struct *work)
1004 {
1005         struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
1006
1007         IWL_DEBUG_SCAN(priv, "Abort scan work\n");
1008
1009         /* We keep scan_check work queued in case when firmware will not
1010          * report back scan completed notification */
1011         mutex_lock(&priv->shrd->mutex);
1012         iwl_scan_cancel_timeout(priv, 200);
1013         mutex_unlock(&priv->shrd->mutex);
1014 }
1015
1016 static void iwl_bg_scan_completed(struct work_struct *work)
1017 {
1018         struct iwl_priv *priv =
1019             container_of(work, struct iwl_priv, scan_completed);
1020         bool aborted;
1021
1022         IWL_DEBUG_SCAN(priv, "Completed scan.\n");
1023
1024         cancel_delayed_work(&priv->scan_check);
1025
1026         mutex_lock(&priv->shrd->mutex);
1027
1028         aborted = test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->shrd->status);
1029         if (aborted)
1030                 IWL_DEBUG_SCAN(priv, "Aborted scan completed.\n");
1031
1032         if (!test_and_clear_bit(STATUS_SCANNING, &priv->shrd->status)) {
1033                 IWL_DEBUG_SCAN(priv, "Scan already completed.\n");
1034                 goto out_settings;
1035         }
1036
1037         if (priv->scan_type == IWL_SCAN_ROC) {
1038                 ieee80211_remain_on_channel_expired(priv->hw);
1039                 priv->hw_roc_channel = NULL;
1040                 schedule_delayed_work(&priv->hw_roc_disable_work, 10 * HZ);
1041         }
1042
1043         if (priv->scan_type != IWL_SCAN_NORMAL && !aborted) {
1044                 int err;
1045
1046                 /* Check if mac80211 requested scan during our internal scan */
1047                 if (priv->scan_request == NULL)
1048                         goto out_complete;
1049
1050                 /* If so request a new scan */
1051                 err = iwl_scan_initiate(priv, priv->scan_vif, IWL_SCAN_NORMAL,
1052                                         priv->scan_request->channels[0]->band);
1053                 if (err) {
1054                         IWL_DEBUG_SCAN(priv,
1055                                 "failed to initiate pending scan: %d\n", err);
1056                         aborted = true;
1057                         goto out_complete;
1058                 }
1059
1060                 goto out;
1061         }
1062
1063 out_complete:
1064         iwl_complete_scan(priv, aborted);
1065
1066 out_settings:
1067         /* Can we still talk to firmware ? */
1068         if (!iwl_is_ready_rf(priv->shrd))
1069                 goto out;
1070
1071         iwlagn_post_scan(priv);
1072
1073 out:
1074         mutex_unlock(&priv->shrd->mutex);
1075 }
1076
1077 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
1078 {
1079         INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
1080         INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
1081         INIT_WORK(&priv->start_internal_scan, iwl_bg_start_internal_scan);
1082         INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
1083 }
1084
1085 void iwl_cancel_scan_deferred_work(struct iwl_priv *priv)
1086 {
1087         cancel_work_sync(&priv->start_internal_scan);
1088         cancel_work_sync(&priv->abort_scan);
1089         cancel_work_sync(&priv->scan_completed);
1090
1091         if (cancel_delayed_work_sync(&priv->scan_check)) {
1092                 mutex_lock(&priv->shrd->mutex);
1093                 iwl_force_scan_end(priv);
1094                 mutex_unlock(&priv->shrd->mutex);
1095         }
1096 }