Merge commit '559fa6e76b27' into perf/urgent
[pandora-kernel.git] / drivers / net / wireless / iwlegacy / 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
40 /* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
41  * sending probe req.  This should be set long enough to hear probe responses
42  * from more than one AP.  */
43 #define IWL_ACTIVE_DWELL_TIME_24    (30)       /* all times in msec */
44 #define IWL_ACTIVE_DWELL_TIME_52    (20)
45
46 #define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
47 #define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
48
49 /* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
50  * Must be set longer than active dwell time.
51  * For the most reliable scan, set > AP beacon interval (typically 100msec). */
52 #define IWL_PASSIVE_DWELL_TIME_24   (20)       /* all times in msec */
53 #define IWL_PASSIVE_DWELL_TIME_52   (10)
54 #define IWL_PASSIVE_DWELL_BASE      (100)
55 #define IWL_CHANNEL_TUNE_TIME       5
56
57 static int iwl_legacy_send_scan_abort(struct iwl_priv *priv)
58 {
59         int ret;
60         struct iwl_rx_packet *pkt;
61         struct iwl_host_cmd cmd = {
62                 .id = REPLY_SCAN_ABORT_CMD,
63                 .flags = CMD_WANT_SKB,
64         };
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_GEO_CONFIGURED, &priv->status) ||
71             !test_bit(STATUS_SCAN_HW, &priv->status) ||
72             test_bit(STATUS_FW_ERROR, &priv->status) ||
73             test_bit(STATUS_EXIT_PENDING, &priv->status))
74                 return -EIO;
75
76         ret = iwl_legacy_send_cmd_sync(priv, &cmd);
77         if (ret)
78                 return ret;
79
80         pkt = (struct iwl_rx_packet *)cmd.reply_page;
81         if (pkt->u.status != CAN_ABORT_STATUS) {
82                 /* The scan abort will return 1 for success or
83                  * 2 for "failure".  A failure condition can be
84                  * due to simply not being in an active scan which
85                  * can occur if we send the scan abort before we
86                  * the microcode has notified us that a scan is
87                  * completed. */
88                 IWL_DEBUG_SCAN(priv, "SCAN_ABORT ret %d.\n", pkt->u.status);
89                 ret = -EIO;
90         }
91
92         iwl_legacy_free_pages(priv, cmd.reply_page);
93         return ret;
94 }
95
96 static void iwl_legacy_complete_scan(struct iwl_priv *priv, bool aborted)
97 {
98         /* check if scan was requested from mac80211 */
99         if (priv->scan_request) {
100                 IWL_DEBUG_SCAN(priv, "Complete scan in mac80211\n");
101                 ieee80211_scan_completed(priv->hw, aborted);
102         }
103
104         priv->is_internal_short_scan = false;
105         priv->scan_vif = NULL;
106         priv->scan_request = NULL;
107 }
108
109 void iwl_legacy_force_scan_end(struct iwl_priv *priv)
110 {
111         lockdep_assert_held(&priv->mutex);
112
113         if (!test_bit(STATUS_SCANNING, &priv->status)) {
114                 IWL_DEBUG_SCAN(priv, "Forcing scan end while not scanning\n");
115                 return;
116         }
117
118         IWL_DEBUG_SCAN(priv, "Forcing scan end\n");
119         clear_bit(STATUS_SCANNING, &priv->status);
120         clear_bit(STATUS_SCAN_HW, &priv->status);
121         clear_bit(STATUS_SCAN_ABORTING, &priv->status);
122         iwl_legacy_complete_scan(priv, true);
123 }
124
125 static void iwl_legacy_do_scan_abort(struct iwl_priv *priv)
126 {
127         int ret;
128
129         lockdep_assert_held(&priv->mutex);
130
131         if (!test_bit(STATUS_SCANNING, &priv->status)) {
132                 IWL_DEBUG_SCAN(priv, "Not performing scan to abort\n");
133                 return;
134         }
135
136         if (test_and_set_bit(STATUS_SCAN_ABORTING, &priv->status)) {
137                 IWL_DEBUG_SCAN(priv, "Scan abort in progress\n");
138                 return;
139         }
140
141         ret = iwl_legacy_send_scan_abort(priv);
142         if (ret) {
143                 IWL_DEBUG_SCAN(priv, "Send scan abort failed %d\n", ret);
144                 iwl_legacy_force_scan_end(priv);
145         } else
146                 IWL_DEBUG_SCAN(priv, "Successfully send scan abort\n");
147 }
148
149 /**
150  * iwl_scan_cancel - Cancel any currently executing HW scan
151  */
152 int iwl_legacy_scan_cancel(struct iwl_priv *priv)
153 {
154         IWL_DEBUG_SCAN(priv, "Queuing abort scan\n");
155         queue_work(priv->workqueue, &priv->abort_scan);
156         return 0;
157 }
158 EXPORT_SYMBOL(iwl_legacy_scan_cancel);
159
160 /**
161  * iwl_legacy_scan_cancel_timeout - Cancel any currently executing HW scan
162  * @ms: amount of time to wait (in milliseconds) for scan to abort
163  *
164  */
165 int iwl_legacy_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
166 {
167         unsigned long timeout = jiffies + msecs_to_jiffies(ms);
168
169         lockdep_assert_held(&priv->mutex);
170
171         IWL_DEBUG_SCAN(priv, "Scan cancel timeout\n");
172
173         iwl_legacy_do_scan_abort(priv);
174
175         while (time_before_eq(jiffies, timeout)) {
176                 if (!test_bit(STATUS_SCAN_HW, &priv->status))
177                         break;
178                 msleep(20);
179         }
180
181         return test_bit(STATUS_SCAN_HW, &priv->status);
182 }
183 EXPORT_SYMBOL(iwl_legacy_scan_cancel_timeout);
184
185 /* Service response to REPLY_SCAN_CMD (0x80) */
186 static void iwl_legacy_rx_reply_scan(struct iwl_priv *priv,
187                               struct iwl_rx_mem_buffer *rxb)
188 {
189 #ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
190         struct iwl_rx_packet *pkt = rxb_addr(rxb);
191         struct iwl_scanreq_notification *notif =
192             (struct iwl_scanreq_notification *)pkt->u.raw;
193
194         IWL_DEBUG_SCAN(priv, "Scan request status = 0x%x\n", notif->status);
195 #endif
196 }
197
198 /* Service SCAN_START_NOTIFICATION (0x82) */
199 static void iwl_legacy_rx_scan_start_notif(struct iwl_priv *priv,
200                                     struct iwl_rx_mem_buffer *rxb)
201 {
202         struct iwl_rx_packet *pkt = rxb_addr(rxb);
203         struct iwl_scanstart_notification *notif =
204             (struct iwl_scanstart_notification *)pkt->u.raw;
205         priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
206         IWL_DEBUG_SCAN(priv, "Scan start: "
207                        "%d [802.11%s] "
208                        "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
209                        notif->channel,
210                        notif->band ? "bg" : "a",
211                        le32_to_cpu(notif->tsf_high),
212                        le32_to_cpu(notif->tsf_low),
213                        notif->status, notif->beacon_timer);
214 }
215
216 /* Service SCAN_RESULTS_NOTIFICATION (0x83) */
217 static void iwl_legacy_rx_scan_results_notif(struct iwl_priv *priv,
218                                       struct iwl_rx_mem_buffer *rxb)
219 {
220 #ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
221         struct iwl_rx_packet *pkt = rxb_addr(rxb);
222         struct iwl_scanresults_notification *notif =
223             (struct iwl_scanresults_notification *)pkt->u.raw;
224
225         IWL_DEBUG_SCAN(priv, "Scan ch.res: "
226                        "%d [802.11%s] "
227                        "(TSF: 0x%08X:%08X) - %d "
228                        "elapsed=%lu usec\n",
229                        notif->channel,
230                        notif->band ? "bg" : "a",
231                        le32_to_cpu(notif->tsf_high),
232                        le32_to_cpu(notif->tsf_low),
233                        le32_to_cpu(notif->statistics[0]),
234                        le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf);
235 #endif
236 }
237
238 /* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
239 static void iwl_legacy_rx_scan_complete_notif(struct iwl_priv *priv,
240                                        struct iwl_rx_mem_buffer *rxb)
241 {
242
243 #ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
244         struct iwl_rx_packet *pkt = rxb_addr(rxb);
245         struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw;
246 #endif
247
248         IWL_DEBUG_SCAN(priv,
249                         "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
250                        scan_notif->scanned_channels,
251                        scan_notif->tsf_low,
252                        scan_notif->tsf_high, scan_notif->status);
253
254         /* The HW is no longer scanning */
255         clear_bit(STATUS_SCAN_HW, &priv->status);
256
257         IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n",
258                        (priv->scan_band == IEEE80211_BAND_2GHZ) ? "2.4" : "5.2",
259                        jiffies_to_msecs(jiffies - priv->scan_start));
260
261         queue_work(priv->workqueue, &priv->scan_completed);
262 }
263
264 void iwl_legacy_setup_rx_scan_handlers(struct iwl_priv *priv)
265 {
266         /* scan handlers */
267         priv->rx_handlers[REPLY_SCAN_CMD] = iwl_legacy_rx_reply_scan;
268         priv->rx_handlers[SCAN_START_NOTIFICATION] =
269                                         iwl_legacy_rx_scan_start_notif;
270         priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
271                                         iwl_legacy_rx_scan_results_notif;
272         priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
273                                         iwl_legacy_rx_scan_complete_notif;
274 }
275 EXPORT_SYMBOL(iwl_legacy_setup_rx_scan_handlers);
276
277 inline u16 iwl_legacy_get_active_dwell_time(struct iwl_priv *priv,
278                                      enum ieee80211_band band,
279                                      u8 n_probes)
280 {
281         if (band == IEEE80211_BAND_5GHZ)
282                 return IWL_ACTIVE_DWELL_TIME_52 +
283                         IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
284         else
285                 return IWL_ACTIVE_DWELL_TIME_24 +
286                         IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
287 }
288 EXPORT_SYMBOL(iwl_legacy_get_active_dwell_time);
289
290 u16 iwl_legacy_get_passive_dwell_time(struct iwl_priv *priv,
291                                enum ieee80211_band band,
292                                struct ieee80211_vif *vif)
293 {
294         struct iwl_rxon_context *ctx;
295         u16 passive = (band == IEEE80211_BAND_2GHZ) ?
296             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
297             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
298
299         if (iwl_legacy_is_any_associated(priv)) {
300                 /*
301                  * If we're associated, we clamp the maximum passive
302                  * dwell time to be 98% of the smallest beacon interval
303                  * (minus 2 * channel tune time)
304                  */
305                 for_each_context(priv, ctx) {
306                         u16 value;
307
308                         if (!iwl_legacy_is_associated_ctx(ctx))
309                                 continue;
310                         value = ctx->vif ? ctx->vif->bss_conf.beacon_int : 0;
311                         if ((value > IWL_PASSIVE_DWELL_BASE) || !value)
312                                 value = IWL_PASSIVE_DWELL_BASE;
313                         value = (value * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
314                         passive = min(value, passive);
315                 }
316         }
317
318         return passive;
319 }
320 EXPORT_SYMBOL(iwl_legacy_get_passive_dwell_time);
321
322 void iwl_legacy_init_scan_params(struct iwl_priv *priv)
323 {
324         u8 ant_idx = fls(priv->hw_params.valid_tx_ant) - 1;
325         if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ])
326                 priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx;
327         if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ])
328                 priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx;
329 }
330 EXPORT_SYMBOL(iwl_legacy_init_scan_params);
331
332 static int __must_check iwl_legacy_scan_initiate(struct iwl_priv *priv,
333                                           struct ieee80211_vif *vif,
334                                           bool internal,
335                                           enum ieee80211_band band)
336 {
337         int ret;
338
339         lockdep_assert_held(&priv->mutex);
340
341         if (WARN_ON(!priv->cfg->ops->utils->request_scan))
342                 return -EOPNOTSUPP;
343
344         cancel_delayed_work(&priv->scan_check);
345
346         if (!iwl_legacy_is_ready_rf(priv)) {
347                 IWL_WARN(priv, "Request scan called when driver not ready.\n");
348                 return -EIO;
349         }
350
351         if (test_bit(STATUS_SCAN_HW, &priv->status)) {
352                 IWL_DEBUG_SCAN(priv,
353                         "Multiple concurrent scan requests in parallel.\n");
354                 return -EBUSY;
355         }
356
357         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
358                 IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n");
359                 return -EBUSY;
360         }
361
362         IWL_DEBUG_SCAN(priv, "Starting %sscan...\n",
363                         internal ? "internal short " : "");
364
365         set_bit(STATUS_SCANNING, &priv->status);
366         priv->is_internal_short_scan = internal;
367         priv->scan_start = jiffies;
368         priv->scan_band = band;
369
370         ret = priv->cfg->ops->utils->request_scan(priv, vif);
371         if (ret) {
372                 clear_bit(STATUS_SCANNING, &priv->status);
373                 priv->is_internal_short_scan = false;
374                 return ret;
375         }
376
377         queue_delayed_work(priv->workqueue, &priv->scan_check,
378                            IWL_SCAN_CHECK_WATCHDOG);
379
380         return 0;
381 }
382
383 int iwl_legacy_mac_hw_scan(struct ieee80211_hw *hw,
384                     struct ieee80211_vif *vif,
385                     struct cfg80211_scan_request *req)
386 {
387         struct iwl_priv *priv = hw->priv;
388         int ret;
389
390         IWL_DEBUG_MAC80211(priv, "enter\n");
391
392         if (req->n_channels == 0)
393                 return -EINVAL;
394
395         mutex_lock(&priv->mutex);
396
397         if (test_bit(STATUS_SCANNING, &priv->status) &&
398             !priv->is_internal_short_scan) {
399                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
400                 ret = -EAGAIN;
401                 goto out_unlock;
402         }
403
404         /* mac80211 will only ask for one band at a time */
405         priv->scan_request = req;
406         priv->scan_vif = vif;
407
408         /*
409          * If an internal scan is in progress, just set
410          * up the scan_request as per above.
411          */
412         if (priv->is_internal_short_scan) {
413                 IWL_DEBUG_SCAN(priv, "SCAN request during internal scan\n");
414                 ret = 0;
415         } else
416                 ret = iwl_legacy_scan_initiate(priv, vif, false,
417                                         req->channels[0]->band);
418
419         IWL_DEBUG_MAC80211(priv, "leave\n");
420
421 out_unlock:
422         mutex_unlock(&priv->mutex);
423
424         return ret;
425 }
426 EXPORT_SYMBOL(iwl_legacy_mac_hw_scan);
427
428 /*
429  * internal short scan, this function should only been called while associated.
430  * It will reset and tune the radio to prevent possible RF related problem
431  */
432 void iwl_legacy_internal_short_hw_scan(struct iwl_priv *priv)
433 {
434         queue_work(priv->workqueue, &priv->start_internal_scan);
435 }
436
437 static void iwl_legacy_bg_start_internal_scan(struct work_struct *work)
438 {
439         struct iwl_priv *priv =
440                 container_of(work, struct iwl_priv, start_internal_scan);
441
442         IWL_DEBUG_SCAN(priv, "Start internal scan\n");
443
444         mutex_lock(&priv->mutex);
445
446         if (priv->is_internal_short_scan == true) {
447                 IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
448                 goto unlock;
449         }
450
451         if (test_bit(STATUS_SCANNING, &priv->status)) {
452                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
453                 goto unlock;
454         }
455
456         if (iwl_legacy_scan_initiate(priv, NULL, true, priv->band))
457                 IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n");
458  unlock:
459         mutex_unlock(&priv->mutex);
460 }
461
462 static void iwl_legacy_bg_scan_check(struct work_struct *data)
463 {
464         struct iwl_priv *priv =
465             container_of(data, struct iwl_priv, scan_check.work);
466
467         IWL_DEBUG_SCAN(priv, "Scan check work\n");
468
469         /* Since we are here firmware does not finish scan and
470          * most likely is in bad shape, so we don't bother to
471          * send abort command, just force scan complete to mac80211 */
472         mutex_lock(&priv->mutex);
473         iwl_legacy_force_scan_end(priv);
474         mutex_unlock(&priv->mutex);
475 }
476
477 /**
478  * iwl_legacy_fill_probe_req - fill in all required fields and IE for probe request
479  */
480
481 u16
482 iwl_legacy_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
483                        const u8 *ta, const u8 *ies, int ie_len, int left)
484 {
485         int len = 0;
486         u8 *pos = NULL;
487
488         /* Make sure there is enough space for the probe request,
489          * two mandatory IEs and the data */
490         left -= 24;
491         if (left < 0)
492                 return 0;
493
494         frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
495         memcpy(frame->da, iwlegacy_bcast_addr, ETH_ALEN);
496         memcpy(frame->sa, ta, ETH_ALEN);
497         memcpy(frame->bssid, iwlegacy_bcast_addr, ETH_ALEN);
498         frame->seq_ctrl = 0;
499
500         len += 24;
501
502         /* ...next IE... */
503         pos = &frame->u.probe_req.variable[0];
504
505         /* fill in our indirect SSID IE */
506         left -= 2;
507         if (left < 0)
508                 return 0;
509         *pos++ = WLAN_EID_SSID;
510         *pos++ = 0;
511
512         len += 2;
513
514         if (WARN_ON(left < ie_len))
515                 return len;
516
517         if (ies && ie_len) {
518                 memcpy(pos, ies, ie_len);
519                 len += ie_len;
520         }
521
522         return (u16)len;
523 }
524 EXPORT_SYMBOL(iwl_legacy_fill_probe_req);
525
526 static void iwl_legacy_bg_abort_scan(struct work_struct *work)
527 {
528         struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
529
530         IWL_DEBUG_SCAN(priv, "Abort scan work\n");
531
532         /* We keep scan_check work queued in case when firmware will not
533          * report back scan completed notification */
534         mutex_lock(&priv->mutex);
535         iwl_legacy_scan_cancel_timeout(priv, 200);
536         mutex_unlock(&priv->mutex);
537 }
538
539 static void iwl_legacy_bg_scan_completed(struct work_struct *work)
540 {
541         struct iwl_priv *priv =
542             container_of(work, struct iwl_priv, scan_completed);
543         bool aborted;
544
545         IWL_DEBUG_SCAN(priv, "Completed %sscan.\n",
546                        priv->is_internal_short_scan ? "internal short " : "");
547
548         cancel_delayed_work(&priv->scan_check);
549
550         mutex_lock(&priv->mutex);
551
552         aborted = test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->status);
553         if (aborted)
554                 IWL_DEBUG_SCAN(priv, "Aborted scan completed.\n");
555
556         if (!test_and_clear_bit(STATUS_SCANNING, &priv->status)) {
557                 IWL_DEBUG_SCAN(priv, "Scan already completed.\n");
558                 goto out_settings;
559         }
560
561         if (priv->is_internal_short_scan && !aborted) {
562                 int err;
563
564                 /* Check if mac80211 requested scan during our internal scan */
565                 if (priv->scan_request == NULL)
566                         goto out_complete;
567
568                 /* If so request a new scan */
569                 err = iwl_legacy_scan_initiate(priv, priv->scan_vif, false,
570                                         priv->scan_request->channels[0]->band);
571                 if (err) {
572                         IWL_DEBUG_SCAN(priv,
573                                 "failed to initiate pending scan: %d\n", err);
574                         aborted = true;
575                         goto out_complete;
576                 }
577
578                 goto out;
579         }
580
581 out_complete:
582         iwl_legacy_complete_scan(priv, aborted);
583
584 out_settings:
585         /* Can we still talk to firmware ? */
586         if (!iwl_legacy_is_ready_rf(priv))
587                 goto out;
588
589         /*
590          * We do not commit power settings while scan is pending,
591          * do it now if the settings changed.
592          */
593         iwl_legacy_power_set_mode(priv, &priv->power_data.sleep_cmd_next,
594                                                                 false);
595         iwl_legacy_set_tx_power(priv, priv->tx_power_next, false);
596
597         priv->cfg->ops->utils->post_scan(priv);
598
599 out:
600         mutex_unlock(&priv->mutex);
601 }
602
603 void iwl_legacy_setup_scan_deferred_work(struct iwl_priv *priv)
604 {
605         INIT_WORK(&priv->scan_completed, iwl_legacy_bg_scan_completed);
606         INIT_WORK(&priv->abort_scan, iwl_legacy_bg_abort_scan);
607         INIT_WORK(&priv->start_internal_scan,
608                                 iwl_legacy_bg_start_internal_scan);
609         INIT_DELAYED_WORK(&priv->scan_check, iwl_legacy_bg_scan_check);
610 }
611 EXPORT_SYMBOL(iwl_legacy_setup_scan_deferred_work);
612
613 void iwl_legacy_cancel_scan_deferred_work(struct iwl_priv *priv)
614 {
615         cancel_work_sync(&priv->start_internal_scan);
616         cancel_work_sync(&priv->abort_scan);
617         cancel_work_sync(&priv->scan_completed);
618
619         if (cancel_delayed_work_sync(&priv->scan_check)) {
620                 mutex_lock(&priv->mutex);
621                 iwl_legacy_force_scan_end(priv);
622                 mutex_unlock(&priv->mutex);
623         }
624 }
625 EXPORT_SYMBOL(iwl_legacy_cancel_scan_deferred_work);