SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/net/wireless/iwlwifi/iwl-scan.c

   1 /******************************************************************************
   2  *
   3  * GPL LICENSE SUMMARY
   4  *
   5  * Copyright(c) 2008 - 2010 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/types.h>
  29 #include <linux/etherdevice.h>
  30 #include <net/mac80211.h>
  31
  32 #include "iwl-eeprom.h"
  33 #include "iwl-dev.h"
  34 #include "iwl-core.h"
  35 #include "iwl-sta.h"
  36 #include "iwl-io.h"
  37 #include "iwl-helpers.h"
  38
  39 /* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
  40  * sending probe req.  This should be set long enough to hear probe responses
  41  * from more than one AP.  */
  42 #define IWL_ACTIVE_DWELL_TIME_24    (30)       /* all times in msec */
  43 #define IWL_ACTIVE_DWELL_TIME_52    (20)
  44
  45 #define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
  46 #define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
  47
  48 /* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
  49  * Must be set longer than active dwell time.
  50  * For the most reliable scan, set > AP beacon interval (typically 100msec). */
  51 #define IWL_PASSIVE_DWELL_TIME_24   (20)       /* all times in msec */
  52 #define IWL_PASSIVE_DWELL_TIME_52   (10)
  53 #define IWL_PASSIVE_DWELL_BASE      (100)
  54 #define IWL_CHANNEL_TUNE_TIME       5
  55
  56
  57
  58 /**
  59  * iwl_scan_cancel - Cancel any currently executing HW scan
  60  *
  61  * NOTE: priv->mutex is not required before calling this function
  62  */
  63 int iwl_scan_cancel(struct iwl_priv *priv)
  64 {
  65         if (!test_bit(STATUS_SCAN_HW, &priv->status)) {
  66                 clear_bit(STATUS_SCANNING, &priv->status);
  67                 return 0;
  68         }
  69
  70         if (test_bit(STATUS_SCANNING, &priv->status)) {
  71                 if (!test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
  72                         IWL_DEBUG_SCAN(priv, "Queuing scan abort.\n");
  73                         set_bit(STATUS_SCAN_ABORTING, &priv->status);
  74                         queue_work(priv->workqueue, &priv->abort_scan);
  75
  76                 } else
  77                         IWL_DEBUG_SCAN(priv, "Scan abort already in progress.\n");
  78
  79                 return test_bit(STATUS_SCANNING, &priv->status);
  80         }
  81
  82         return 0;
  83 }
  84 EXPORT_SYMBOL(iwl_scan_cancel);
  85 /**
  86  * iwl_scan_cancel_timeout - Cancel any currently executing HW scan
  87  * @ms: amount of time to wait (in milliseconds) for scan to abort
  88  *
  89  * NOTE: priv->mutex must be held before calling this function
  90  */
  91 int iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
  92 {
  93         unsigned long now = jiffies;
  94         int ret;
  95
  96         ret = iwl_scan_cancel(priv);
  97         if (ret && ms) {
  98                 mutex_unlock(&priv->mutex);
  99                 while (!time_after(jiffies, now + msecs_to_jiffies(ms)) &&
 100                                 test_bit(STATUS_SCANNING, &priv->status))
 101                         msleep(1);
 102                 mutex_lock(&priv->mutex);
 103
 104                 return test_bit(STATUS_SCANNING, &priv->status);
 105         }
 106
 107         return ret;
 108 }
 109 EXPORT_SYMBOL(iwl_scan_cancel_timeout);
 110
 111 static int iwl_send_scan_abort(struct iwl_priv *priv)
 112 {
 113         int ret = 0;
 114         struct iwl_rx_packet *pkt;
 115         struct iwl_host_cmd cmd = {
 116                 .id = REPLY_SCAN_ABORT_CMD,
 117                 .flags = CMD_WANT_SKB,
 118         };
 119
 120         /* If there isn't a scan actively going on in the hardware
 121          * then we are in between scan bands and not actually
 122          * actively scanning, so don't send the abort command */
 123         if (!test_bit(STATUS_SCAN_HW, &priv->status)) {
 124                 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
 125                 return 0;
 126         }
 127
 128         ret = iwl_send_cmd_sync(priv, &cmd);
 129         if (ret) {
 130                 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
 131                 return ret;
 132         }
 133
 134         pkt = (struct iwl_rx_packet *)cmd.reply_page;
 135         if (pkt->u.status != CAN_ABORT_STATUS) {
 136                 /* The scan abort will return 1 for success or
 137                  * 2 for "failure".  A failure condition can be
 138                  * due to simply not being in an active scan which
 139                  * can occur if we send the scan abort before we
 140                  * the microcode has notified us that a scan is
 141                  * completed. */
 142                 IWL_DEBUG_INFO(priv, "SCAN_ABORT returned %d.\n", pkt->u.status);
 143                 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
 144                 clear_bit(STATUS_SCAN_HW, &priv->status);
 145         }
 146
 147         iwl_free_pages(priv, cmd.reply_page);
 148
 149         return ret;
 150 }
 151
 152 /* Service response to REPLY_SCAN_CMD (0x80) */
 153 static void iwl_rx_reply_scan(struct iwl_priv *priv,
 154                               struct iwl_rx_mem_buffer *rxb)
 155 {
 156 #ifdef CONFIG_IWLWIFI_DEBUG
 157         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 158         struct iwl_scanreq_notification *notif =
 159             (struct iwl_scanreq_notification *)pkt->u.raw;
 160
 161         IWL_DEBUG_RX(priv, "Scan request status = 0x%x\n", notif->status);
 162 #endif
 163 }
 164
 165 /* Service SCAN_START_NOTIFICATION (0x82) */
 166 static void iwl_rx_scan_start_notif(struct iwl_priv *priv,
 167                                     struct iwl_rx_mem_buffer *rxb)
 168 {
 169         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 170         struct iwl_scanstart_notification *notif =
 171             (struct iwl_scanstart_notification *)pkt->u.raw;
 172         priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
 173         IWL_DEBUG_SCAN(priv, "Scan start: "
 174                        "%d [802.11%s] "
 175                        "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
 176                        notif->channel,
 177                        notif->band ? "bg" : "a",
 178                        le32_to_cpu(notif->tsf_high),
 179                        le32_to_cpu(notif->tsf_low),
 180                        notif->status, notif->beacon_timer);
 181 }
 182
 183 /* Service SCAN_RESULTS_NOTIFICATION (0x83) */
 184 static void iwl_rx_scan_results_notif(struct iwl_priv *priv,
 185                                       struct iwl_rx_mem_buffer *rxb)
 186 {
 187 #ifdef CONFIG_IWLWIFI_DEBUG
 188         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 189         struct iwl_scanresults_notification *notif =
 190             (struct iwl_scanresults_notification *)pkt->u.raw;
 191
 192         IWL_DEBUG_SCAN(priv, "Scan ch.res: "
 193                        "%d [802.11%s] "
 194                        "(TSF: 0x%08X:%08X) - %d "
 195                        "elapsed=%lu usec\n",
 196                        notif->channel,
 197                        notif->band ? "bg" : "a",
 198                        le32_to_cpu(notif->tsf_high),
 199                        le32_to_cpu(notif->tsf_low),
 200                        le32_to_cpu(notif->statistics[0]),
 201                        le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf);
 202 #endif
 203
 204         if (!priv->is_internal_short_scan)
 205                 priv->next_scan_jiffies = 0;
 206 }
 207
 208 /* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
 209 static void iwl_rx_scan_complete_notif(struct iwl_priv *priv,
 210                                        struct iwl_rx_mem_buffer *rxb)
 211 {
 212 #ifdef CONFIG_IWLWIFI_DEBUG
 213         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 214         struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw;
 215
 216         IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
 217                        scan_notif->scanned_channels,
 218                        scan_notif->tsf_low,
 219                        scan_notif->tsf_high, scan_notif->status);
 220 #endif
 221
 222         /* The HW is no longer scanning */
 223         clear_bit(STATUS_SCAN_HW, &priv->status);
 224
 225         IWL_DEBUG_INFO(priv, "Scan pass on %sGHz took %dms\n",
 226                        (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ)) ?
 227                                                 "2.4" : "5.2",
 228                        jiffies_to_msecs(elapsed_jiffies
 229                                         (priv->scan_pass_start, jiffies)));
 230
 231         /* Remove this scanned band from the list of pending
 232          * bands to scan, band G precedes A in order of scanning
 233          * as seen in iwl_bg_request_scan */
 234         if (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ))
 235                 priv->scan_bands &= ~BIT(IEEE80211_BAND_2GHZ);
 236         else if (priv->scan_bands &  BIT(IEEE80211_BAND_5GHZ))
 237                 priv->scan_bands &= ~BIT(IEEE80211_BAND_5GHZ);
 238
 239         /* If a request to abort was given, or the scan did not succeed
 240          * then we reset the scan state machine and terminate,
 241          * re-queuing another scan if one has been requested */
 242         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
 243                 IWL_DEBUG_INFO(priv, "Aborted scan completed.\n");
 244                 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
 245         } else {
 246                 /* If there are more bands on this scan pass reschedule */
 247                 if (priv->scan_bands)
 248                         goto reschedule;
 249         }
 250
 251         if (!priv->is_internal_short_scan)
 252                 priv->next_scan_jiffies = 0;
 253         else
 254                 priv->last_internal_scan_jiffies = jiffies;
 255
 256         IWL_DEBUG_INFO(priv, "Setting scan to off\n");
 257
 258         clear_bit(STATUS_SCANNING, &priv->status);
 259
 260         IWL_DEBUG_INFO(priv, "Scan took %dms\n",
 261                 jiffies_to_msecs(elapsed_jiffies(priv->scan_start, jiffies)));
 262
 263         queue_work(priv->workqueue, &priv->scan_completed);
 264
 265         return;
 266
 267 reschedule:
 268         priv->scan_pass_start = jiffies;
 269         queue_work(priv->workqueue, &priv->request_scan);
 270 }
 271
 272 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
 273 {
 274         /* scan handlers */
 275         priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
 276         priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
 277         priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
 278                                         iwl_rx_scan_results_notif;
 279         priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
 280                                         iwl_rx_scan_complete_notif;
 281 }
 282 EXPORT_SYMBOL(iwl_setup_rx_scan_handlers);
 283
 284 inline u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
 285                                      enum ieee80211_band band,
 286                                      u8 n_probes)
 287 {
 288         if (band == IEEE80211_BAND_5GHZ)
 289                 return IWL_ACTIVE_DWELL_TIME_52 +
 290                         IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
 291         else
 292                 return IWL_ACTIVE_DWELL_TIME_24 +
 293                         IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
 294 }
 295 EXPORT_SYMBOL(iwl_get_active_dwell_time);
 296
 297 u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
 298                                enum ieee80211_band band)
 299 {
 300         u16 passive = (band == IEEE80211_BAND_2GHZ) ?
 301             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
 302             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
 303
 304         if (iwl_is_associated(priv)) {
 305                 /* If we're associated, we clamp the maximum passive
 306                  * dwell time to be 98% of the beacon interval (minus
 307                  * 2 * channel tune time) */
 308                 passive = priv->beacon_int;
 309                 if ((passive > IWL_PASSIVE_DWELL_BASE) || !passive)
 310                         passive = IWL_PASSIVE_DWELL_BASE;
 311                 passive = (passive * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
 312         }
 313
 314         return passive;
 315 }
 316 EXPORT_SYMBOL(iwl_get_passive_dwell_time);
 317
 318 static int iwl_get_single_channel_for_scan(struct iwl_priv *priv,
 319                                      enum ieee80211_band band,
 320                                      struct iwl_scan_channel *scan_ch)
 321 {
 322         const struct ieee80211_supported_band *sband;
 323         const struct iwl_channel_info *ch_info;
 324         u16 passive_dwell = 0;
 325         u16 active_dwell = 0;
 326         int i, added = 0;
 327         u16 channel = 0;
 328
 329         sband = iwl_get_hw_mode(priv, band);
 330         if (!sband) {
 331                 IWL_ERR(priv, "invalid band\n");
 332                 return added;
 333         }
 334
 335         active_dwell = iwl_get_active_dwell_time(priv, band, 0);
 336         passive_dwell = iwl_get_passive_dwell_time(priv, band);
 337
 338         if (passive_dwell <= active_dwell)
 339                 passive_dwell = active_dwell + 1;
 340
 341         /* only scan single channel, good enough to reset the RF */
 342         /* pick the first valid not in-use channel */
 343         if (band == IEEE80211_BAND_5GHZ) {
 344                 for (i = 14; i < priv->channel_count; i++) {
 345                         if (priv->channel_info[i].channel !=
 346                             le16_to_cpu(priv->staging_rxon.channel)) {
 347                                 channel = priv->channel_info[i].channel;
 348                                 ch_info = iwl_get_channel_info(priv,
 349                                         band, channel);
 350                                 if (is_channel_valid(ch_info))
 351                                         break;
 352                         }
 353                 }
 354         } else {
 355                 for (i = 0; i < 14; i++) {
 356                         if (priv->channel_info[i].channel !=
 357                             le16_to_cpu(priv->staging_rxon.channel)) {
 358                                         channel =
 359                                                 priv->channel_info[i].channel;
 360                                         ch_info = iwl_get_channel_info(priv,
 361                                                 band, channel);
 362                                         if (is_channel_valid(ch_info))
 363                                                 break;
 364                         }
 365                 }
 366         }
 367         if (channel) {
 368                 scan_ch->channel = cpu_to_le16(channel);
 369                 scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 370                 scan_ch->active_dwell = cpu_to_le16(active_dwell);
 371                 scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
 372                 /* Set txpower levels to defaults */
 373                 scan_ch->dsp_atten = 110;
 374                 if (band == IEEE80211_BAND_5GHZ)
 375                         scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 376                 else
 377                         scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 378                 added++;
 379         } else
 380                 IWL_ERR(priv, "no valid channel found\n");
 381         return added;
 382 }
 383
 384 static int iwl_get_channels_for_scan(struct iwl_priv *priv,
 385                                      enum ieee80211_band band,
 386                                      u8 is_active, u8 n_probes,
 387                                      struct iwl_scan_channel *scan_ch)
 388 {
 389         struct ieee80211_channel *chan;
 390         const struct ieee80211_supported_band *sband;
 391         const struct iwl_channel_info *ch_info;
 392         u16 passive_dwell = 0;
 393         u16 active_dwell = 0;
 394         int added, i;
 395         u16 channel;
 396
 397         sband = iwl_get_hw_mode(priv, band);
 398         if (!sband)
 399                 return 0;
 400
 401         active_dwell = iwl_get_active_dwell_time(priv, band, n_probes);
 402         passive_dwell = iwl_get_passive_dwell_time(priv, band);
 403
 404         if (passive_dwell <= active_dwell)
 405                 passive_dwell = active_dwell + 1;
 406
 407         for (i = 0, added = 0; i < priv->scan_request->n_channels; i++) {
 408                 chan = priv->scan_request->channels[i];
 409
 410                 if (chan->band != band)
 411                         continue;
 412
 413                 channel = ieee80211_frequency_to_channel(chan->center_freq);
 414                 scan_ch->channel = cpu_to_le16(channel);
 415
 416                 ch_info = iwl_get_channel_info(priv, band, channel);
 417                 if (!is_channel_valid(ch_info)) {
 418                         IWL_DEBUG_SCAN(priv, "Channel %d is INVALID for this band.\n",
 419                                         channel);
 420                         continue;
 421                 }
 422
 423                 if (!is_active || is_channel_passive(ch_info) ||
 424                     (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN))
 425                         scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 426                 else
 427                         scan_ch->type = SCAN_CHANNEL_TYPE_ACTIVE;
 428
 429                 if (n_probes)
 430                         scan_ch->type |= IWL_SCAN_PROBE_MASK(n_probes);
 431
 432                 scan_ch->active_dwell = cpu_to_le16(active_dwell);
 433                 scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
 434
 435                 /* Set txpower levels to defaults */
 436                 scan_ch->dsp_atten = 110;
 437
 438                 /* NOTE: if we were doing 6Mb OFDM for scans we'd use
 439                  * power level:
 440                  * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
 441                  */
 442                 if (band == IEEE80211_BAND_5GHZ)
 443                         scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 444                 else
 445                         scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 446
 447                 IWL_DEBUG_SCAN(priv, "Scanning ch=%d prob=0x%X [%s %d]\n",
 448                                channel, le32_to_cpu(scan_ch->type),
 449                                (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
 450                                 "ACTIVE" : "PASSIVE",
 451                                (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
 452                                active_dwell : passive_dwell);
 453
 454                 scan_ch++;
 455                 added++;
 456         }
 457
 458         IWL_DEBUG_SCAN(priv, "total channels to scan %d \n", added);
 459         return added;
 460 }
 461
 462 void iwl_init_scan_params(struct iwl_priv *priv)
 463 {
 464         u8 ant_idx = fls(priv->hw_params.valid_tx_ant) - 1;
 465         if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ])
 466                 priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx;
 467         if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ])
 468                 priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx;
 469 }
 470 EXPORT_SYMBOL(iwl_init_scan_params);
 471
 472 static int iwl_scan_initiate(struct iwl_priv *priv)
 473 {
 474         if (!iwl_is_ready_rf(priv)) {
 475                 IWL_DEBUG_SCAN(priv, "Aborting scan due to not ready.\n");
 476                 return -EIO;
 477         }
 478
 479         if (test_bit(STATUS_SCANNING, &priv->status)) {
 480                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
 481                 return -EAGAIN;
 482         }
 483
 484         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
 485                 IWL_DEBUG_SCAN(priv, "Scan request while abort pending\n");
 486                 return -EAGAIN;
 487         }
 488
 489         IWL_DEBUG_INFO(priv, "Starting scan...\n");
 490         set_bit(STATUS_SCANNING, &priv->status);
 491         priv->is_internal_short_scan = false;
 492         priv->scan_start = jiffies;
 493         priv->scan_pass_start = priv->scan_start;
 494
 495         queue_work(priv->workqueue, &priv->request_scan);
 496
 497         return 0;
 498 }
 499
 500 #define IWL_DELAY_NEXT_SCAN (HZ*2)
 501
 502 int iwl_mac_hw_scan(struct ieee80211_hw *hw,
 503                      struct cfg80211_scan_request *req)
 504 {
 505         unsigned long flags;
 506         struct iwl_priv *priv = hw->priv;
 507         int ret, i;
 508
 509         IWL_DEBUG_MAC80211(priv, "enter\n");
 510
 511         mutex_lock(&priv->mutex);
 512         spin_lock_irqsave(&priv->lock, flags);
 513
 514         if (!iwl_is_ready_rf(priv)) {
 515                 ret = -EIO;
 516                 IWL_DEBUG_MAC80211(priv, "leave - not ready or exit pending\n");
 517                 goto out_unlock;
 518         }
 519
 520         /* We don't schedule scan within next_scan_jiffies period.
 521          * Avoid scanning during possible EAPOL exchange, return
 522          * success immediately.
 523          */
 524         if (priv->next_scan_jiffies &&
 525             time_after(priv->next_scan_jiffies, jiffies)) {
 526                 IWL_DEBUG_SCAN(priv, "scan rejected: within next scan period\n");
 527                 queue_work(priv->workqueue, &priv->scan_completed);
 528                 ret = 0;
 529                 goto out_unlock;
 530         }
 531
 532         priv->scan_bands = 0;
 533         for (i = 0; i < req->n_channels; i++)
 534                 priv->scan_bands |= BIT(req->channels[i]->band);
 535
 536         priv->scan_request = req;
 537
 538         ret = iwl_scan_initiate(priv);
 539
 540         IWL_DEBUG_MAC80211(priv, "leave\n");
 541
 542 out_unlock:
 543         spin_unlock_irqrestore(&priv->lock, flags);
 544         mutex_unlock(&priv->mutex);
 545
 546         return ret;
 547 }
 548 EXPORT_SYMBOL(iwl_mac_hw_scan);
 549
 550 /*
 551  * internal short scan, this function should only been called while associated.
 552  * It will reset and tune the radio to prevent possible RF related problem
 553  */
 554 #define IWL_DELAY_NEXT_INTERNAL_SCAN (HZ*1)
 555
 556 int iwl_internal_short_hw_scan(struct iwl_priv *priv)
 557 {
 558         int ret = 0;
 559
 560         if (!iwl_is_ready_rf(priv)) {
 561                 ret = -EIO;
 562                 IWL_DEBUG_SCAN(priv, "not ready or exit pending\n");
 563                 goto out;
 564         }
 565         if (test_bit(STATUS_SCANNING, &priv->status)) {
 566                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
 567                 ret = -EAGAIN;
 568                 goto out;
 569         }
 570         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
 571                 IWL_DEBUG_SCAN(priv, "Scan request while abort pending\n");
 572                 ret = -EAGAIN;
 573                 goto out;
 574         }
 575         if (priv->last_internal_scan_jiffies &&
 576             time_after(priv->last_internal_scan_jiffies +
 577                        IWL_DELAY_NEXT_INTERNAL_SCAN, jiffies)) {
 578                 IWL_DEBUG_SCAN(priv, "internal scan rejected\n");
 579                 goto out;
 580         }
 581
 582         priv->scan_bands = 0;
 583         if (priv->band == IEEE80211_BAND_5GHZ)
 584                 priv->scan_bands |= BIT(IEEE80211_BAND_5GHZ);
 585         else
 586                 priv->scan_bands |= BIT(IEEE80211_BAND_2GHZ);
 587
 588         IWL_DEBUG_SCAN(priv, "Start internal short scan...\n");
 589         set_bit(STATUS_SCANNING, &priv->status);
 590         priv->is_internal_short_scan = true;
 591         queue_work(priv->workqueue, &priv->request_scan);
 592
 593 out:
 594         return ret;
 595 }
 596 EXPORT_SYMBOL(iwl_internal_short_hw_scan);
 597
 598 #define IWL_SCAN_CHECK_WATCHDOG (7 * HZ)
 599
 600 void iwl_bg_scan_check(struct work_struct *data)
 601 {
 602         struct iwl_priv *priv =
 603             container_of(data, struct iwl_priv, scan_check.work);
 604
 605         if (test_bit(STATUS_EXIT_PENDING, &priv->status))
 606                 return;
 607
 608         mutex_lock(&priv->mutex);
 609         if (test_bit(STATUS_SCANNING, &priv->status) ||
 610             test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
 611                 IWL_DEBUG_SCAN(priv, "Scan completion watchdog resetting "
 612                         "adapter (%dms)\n",
 613                         jiffies_to_msecs(IWL_SCAN_CHECK_WATCHDOG));
 614
 615                 if (!test_bit(STATUS_EXIT_PENDING, &priv->status))
 616                         iwl_send_scan_abort(priv);
 617         }
 618         mutex_unlock(&priv->mutex);
 619 }
 620 EXPORT_SYMBOL(iwl_bg_scan_check);
 621
 622 /**
 623  * iwl_fill_probe_req - fill in all required fields and IE for probe request
 624  */
 625
 626 u16 iwl_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
 627                        const u8 *ies, int ie_len, int left)
 628 {
 629         int len = 0;
 630         u8 *pos = NULL;
 631
 632         /* Make sure there is enough space for the probe request,
 633          * two mandatory IEs and the data */
 634         left -= 24;
 635         if (left < 0)
 636                 return 0;
 637
 638         frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
 639         memcpy(frame->da, iwl_bcast_addr, ETH_ALEN);
 640         memcpy(frame->sa, priv->mac_addr, ETH_ALEN);
 641         memcpy(frame->bssid, iwl_bcast_addr, ETH_ALEN);
 642         frame->seq_ctrl = 0;
 643
 644         len += 24;
 645
 646         /* ...next IE... */
 647         pos = &frame->u.probe_req.variable[0];
 648
 649         /* fill in our indirect SSID IE */
 650         left -= 2;
 651         if (left < 0)
 652                 return 0;
 653         *pos++ = WLAN_EID_SSID;
 654         if (!priv->is_internal_short_scan &&
 655             priv->scan_request->n_ssids) {
 656                 struct cfg80211_ssid *ssid =
 657                         priv->scan_request->ssids;
 658
 659                 /* Broadcast if ssid_len is 0 */
 660                 *pos++ = ssid->ssid_len;
 661                 memcpy(pos, ssid->ssid, ssid->ssid_len);
 662                 pos += ssid->ssid_len;
 663                 len += 2 + ssid->ssid_len;
 664         } else {
 665                 *pos++ = 0;
 666                 len += 2;
 667         }
 668
 669         if (WARN_ON(left < ie_len))
 670                 return len;
 671
 672         if (ies)
 673                 memcpy(pos, ies, ie_len);
 674         len += ie_len;
 675         left -= ie_len;
 676
 677         return (u16)len;
 678 }
 679 EXPORT_SYMBOL(iwl_fill_probe_req);
 680
 681 static void iwl_bg_request_scan(struct work_struct *data)
 682 {
 683         struct iwl_priv *priv =
 684             container_of(data, struct iwl_priv, request_scan);
 685         struct iwl_host_cmd cmd = {
 686                 .id = REPLY_SCAN_CMD,
 687                 .len = sizeof(struct iwl_scan_cmd),
 688                 .flags = CMD_SIZE_HUGE,
 689         };
 690         struct iwl_scan_cmd *scan;
 691         struct ieee80211_conf *conf = NULL;
 692         int ret = 0;
 693         u32 rate_flags = 0;
 694         u16 cmd_len;
 695         u16 rx_chain = 0;
 696         enum ieee80211_band band;
 697         u8 n_probes = 0;
 698         u8 rx_ant = priv->hw_params.valid_rx_ant;
 699         u8 rate;
 700         bool is_active = false;
 701         int  chan_mod;
 702         u8 active_chains;
 703
 704         conf = ieee80211_get_hw_conf(priv->hw);
 705
 706         mutex_lock(&priv->mutex);
 707
 708         cancel_delayed_work(&priv->scan_check);
 709
 710         if (!iwl_is_ready(priv)) {
 711                 IWL_WARN(priv, "request scan called when driver not ready.\n");
 712                 goto done;
 713         }
 714
 715         /* Make sure the scan wasn't canceled before this queued work
 716          * was given the chance to run... */
 717         if (!test_bit(STATUS_SCANNING, &priv->status))
 718                 goto done;
 719
 720         /* This should never be called or scheduled if there is currently
 721          * a scan active in the hardware. */
 722         if (test_bit(STATUS_SCAN_HW, &priv->status)) {
 723                 IWL_DEBUG_INFO(priv, "Multiple concurrent scan requests in parallel. "
 724                                "Ignoring second request.\n");
 725                 ret = -EIO;
 726                 goto done;
 727         }
 728
 729         if (test_bit(STATUS_EXIT_PENDING, &priv->status)) {
 730                 IWL_DEBUG_SCAN(priv, "Aborting scan due to device shutdown\n");
 731                 goto done;
 732         }
 733
 734         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
 735                 IWL_DEBUG_HC(priv, "Scan request while abort pending.  Queuing.\n");
 736                 goto done;
 737         }
 738
 739         if (iwl_is_rfkill(priv)) {
 740                 IWL_DEBUG_HC(priv, "Aborting scan due to RF Kill activation\n");
 741                 goto done;
 742         }
 743
 744         if (!test_bit(STATUS_READY, &priv->status)) {
 745                 IWL_DEBUG_HC(priv, "Scan request while uninitialized.  Queuing.\n");
 746                 goto done;
 747         }
 748
 749         if (!priv->scan_bands) {
 750                 IWL_DEBUG_HC(priv, "Aborting scan due to no requested bands\n");
 751                 goto done;
 752         }
 753
 754         if (!priv->scan) {
 755                 priv->scan = kmalloc(sizeof(struct iwl_scan_cmd) +
 756                                      IWL_MAX_SCAN_SIZE, GFP_KERNEL);
 757                 if (!priv->scan) {
 758                         ret = -ENOMEM;
 759                         goto done;
 760                 }
 761         }
 762         scan = priv->scan;
 763         memset(scan, 0, sizeof(struct iwl_scan_cmd) + IWL_MAX_SCAN_SIZE);
 764
 765         scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH;
 766         scan->quiet_time = IWL_ACTIVE_QUIET_TIME;
 767
 768         if (iwl_is_associated(priv)) {
 769                 u16 interval = 0;
 770                 u32 extra;
 771                 u32 suspend_time = 100;
 772                 u32 scan_suspend_time = 100;
 773                 unsigned long flags;
 774
 775                 IWL_DEBUG_INFO(priv, "Scanning while associated...\n");
 776                 spin_lock_irqsave(&priv->lock, flags);
 777                 interval = priv->beacon_int;
 778                 spin_unlock_irqrestore(&priv->lock, flags);
 779
 780                 scan->suspend_time = 0;
 781                 scan->max_out_time = cpu_to_le32(200 * 1024);
 782                 if (!interval)
 783                         interval = suspend_time;
 784
 785                 extra = (suspend_time / interval) << 22;
 786                 scan_suspend_time = (extra |
 787                     ((suspend_time % interval) * 1024));
 788                 scan->suspend_time = cpu_to_le32(scan_suspend_time);
 789                 IWL_DEBUG_SCAN(priv, "suspend_time 0x%X beacon interval %d\n",
 790                                scan_suspend_time, interval);
 791         }
 792
 793         if (priv->is_internal_short_scan) {
 794                 IWL_DEBUG_SCAN(priv, "Start internal passive scan.\n");
 795         } else if (priv->scan_request->n_ssids) {
 796                 IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
 797                 /*
 798                  * The first SSID to scan is stuffed into the probe request
 799                  * template and the remaining ones are handled through the
 800                  * direct_scan array.
 801                  */
 802                 if (priv->scan_request->n_ssids > 1) {
 803                         int i, p = 0;
 804                         for (i = 1; i < priv->scan_request->n_ssids; i++) {
 805                                 if (!priv->scan_request->ssids[i].ssid_len)
 806                                         continue;
 807                                 scan->direct_scan[p].id = WLAN_EID_SSID;
 808                                 scan->direct_scan[p].len =
 809                                         priv->scan_request->ssids[i].ssid_len;
 810                                 memcpy(scan->direct_scan[p].ssid,
 811                                        priv->scan_request->ssids[i].ssid,
 812                                        priv->scan_request->ssids[i].ssid_len);
 813                                 n_probes++;
 814                                 p++;
 815                         }
 816                 }
 817                 is_active = true;
 818         } else
 819                 IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
 820
 821         scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
 822         scan->tx_cmd.sta_id = priv->hw_params.bcast_sta_id;
 823         scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
 824
 825
 826         if (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ)) {
 827                 band = IEEE80211_BAND_2GHZ;
 828                 scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK;
 829                 chan_mod = le32_to_cpu(priv->active_rxon.flags & RXON_FLG_CHANNEL_MODE_MSK)
 830                                        >> RXON_FLG_CHANNEL_MODE_POS;
 831                 if (chan_mod == CHANNEL_MODE_PURE_40) {
 832                         rate = IWL_RATE_6M_PLCP;
 833                 } else {
 834                         rate = IWL_RATE_1M_PLCP;
 835                         rate_flags = RATE_MCS_CCK_MSK;
 836                 }
 837                 scan->good_CRC_th = 0;
 838         } else if (priv->scan_bands & BIT(IEEE80211_BAND_5GHZ)) {
 839                 band = IEEE80211_BAND_5GHZ;
 840                 rate = IWL_RATE_6M_PLCP;
 841                 /*
 842                  * If active scaning is requested but a certain channel
 843                  * is marked passive, we can do active scanning if we
 844                  * detect transmissions.
 845                  */
 846                 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH : 0;
 847
 848                 /* Force use of chains B and C (0x6) for scan Rx for 4965
 849                  * Avoid A (0x1) because of its off-channel reception on A-band.
 850                  */
 851                 if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) == CSR_HW_REV_TYPE_4965)
 852                         rx_ant = ANT_BC;
 853         } else {
 854                 IWL_WARN(priv, "Invalid scan band count\n");
 855                 goto done;
 856         }
 857
 858         priv->scan_tx_ant[band] =
 859                          iwl_toggle_tx_ant(priv, priv->scan_tx_ant[band]);
 860         rate_flags |= iwl_ant_idx_to_flags(priv->scan_tx_ant[band]);
 861         scan->tx_cmd.rate_n_flags = iwl_hw_set_rate_n_flags(rate, rate_flags);
 862
 863         /* In power save mode use one chain, otherwise use all chains */
 864         if (test_bit(STATUS_POWER_PMI, &priv->status)) {
 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         /* MIMO is not used here, but value is required */
 877         rx_chain |= priv->hw_params.valid_rx_ant << RXON_RX_CHAIN_VALID_POS;
 878         rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
 879         rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS;
 880         rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
 881         scan->rx_chain = cpu_to_le16(rx_chain);
 882         if (!priv->is_internal_short_scan) {
 883                 cmd_len = iwl_fill_probe_req(priv,
 884                                         (struct ieee80211_mgmt *)scan->data,
 885                                         priv->scan_request->ie,
 886                                         priv->scan_request->ie_len,
 887                                         IWL_MAX_SCAN_SIZE - sizeof(*scan));
 888         } else {
 889                 cmd_len = iwl_fill_probe_req(priv,
 890                                         (struct ieee80211_mgmt *)scan->data,
 891                                         NULL, 0,
 892                                         IWL_MAX_SCAN_SIZE - sizeof(*scan));
 893
 894         }
 895         scan->tx_cmd.len = cpu_to_le16(cmd_len);
 896         if (iwl_is_monitor_mode(priv))
 897                 scan->filter_flags = RXON_FILTER_PROMISC_MSK;
 898
 899         scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK |
 900                                RXON_FILTER_BCON_AWARE_MSK);
 901
 902         if (priv->is_internal_short_scan) {
 903                 scan->channel_count =
 904                         iwl_get_single_channel_for_scan(priv, band,
 905                                 (void *)&scan->data[le16_to_cpu(
 906                                 scan->tx_cmd.len)]);
 907         } else {
 908                 scan->channel_count =
 909                         iwl_get_channels_for_scan(priv, band,
 910                                 is_active, n_probes,
 911                                 (void *)&scan->data[le16_to_cpu(
 912                                 scan->tx_cmd.len)]);
 913         }
 914         if (scan->channel_count == 0) {
 915                 IWL_DEBUG_SCAN(priv, "channel count %d\n", scan->channel_count);
 916                 goto done;
 917         }
 918
 919         cmd.len += le16_to_cpu(scan->tx_cmd.len) +
 920             scan->channel_count * sizeof(struct iwl_scan_channel);
 921         cmd.data = scan;
 922         scan->len = cpu_to_le16(cmd.len);
 923
 924         set_bit(STATUS_SCAN_HW, &priv->status);
 925         ret = iwl_send_cmd_sync(priv, &cmd);
 926         if (ret)
 927                 goto done;
 928
 929         queue_delayed_work(priv->workqueue, &priv->scan_check,
 930                            IWL_SCAN_CHECK_WATCHDOG);
 931
 932         mutex_unlock(&priv->mutex);
 933         return;
 934
 935  done:
 936         /* Cannot perform scan. Make sure we clear scanning
 937         * bits from status so next scan request can be performed.
 938         * If we don't clear scanning status bit here all next scan
 939         * will fail
 940         */
 941         clear_bit(STATUS_SCAN_HW, &priv->status);
 942         clear_bit(STATUS_SCANNING, &priv->status);
 943         /* inform mac80211 scan aborted */
 944         queue_work(priv->workqueue, &priv->scan_completed);
 945         mutex_unlock(&priv->mutex);
 946 }
 947
 948 void iwl_bg_abort_scan(struct work_struct *work)
 949 {
 950         struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
 951
 952         if (!test_bit(STATUS_READY, &priv->status) ||
 953             !test_bit(STATUS_GEO_CONFIGURED, &priv->status))
 954                 return;
 955
 956         mutex_lock(&priv->mutex);
 957
 958         set_bit(STATUS_SCAN_ABORTING, &priv->status);
 959         iwl_send_scan_abort(priv);
 960
 961         mutex_unlock(&priv->mutex);
 962 }
 963 EXPORT_SYMBOL(iwl_bg_abort_scan);
 964
 965 void iwl_bg_scan_completed(struct work_struct *work)
 966 {
 967         struct iwl_priv *priv =
 968             container_of(work, struct iwl_priv, scan_completed);
 969
 970         IWL_DEBUG_SCAN(priv, "SCAN complete scan\n");
 971
 972         cancel_delayed_work(&priv->scan_check);
 973
 974         if (!priv->is_internal_short_scan)
 975                 ieee80211_scan_completed(priv->hw, false);
 976         else {
 977                 priv->is_internal_short_scan = false;
 978                 IWL_DEBUG_SCAN(priv, "internal short scan completed\n");
 979         }
 980
 981         if (test_bit(STATUS_EXIT_PENDING, &priv->status))
 982                 return;
 983
 984         /* Since setting the TXPOWER may have been deferred while
 985          * performing the scan, fire one off */
 986         mutex_lock(&priv->mutex);
 987         iwl_set_tx_power(priv, priv->tx_power_user_lmt, true);
 988         mutex_unlock(&priv->mutex);
 989 }
 990 EXPORT_SYMBOL(iwl_bg_scan_completed);
 991
 992 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
 993 {
 994         INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
 995         INIT_WORK(&priv->request_scan, iwl_bg_request_scan);
 996         INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
 997         INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
 998 }
 999 EXPORT_SYMBOL(iwl_setup_scan_deferred_work);
1000