iwlwifi: fix set_tx_power vs scan
[pandora-kernel.git] / 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>
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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_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_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_free_pages(priv, cmd.reply_page);
93         return ret;
94 }
95
96 static void iwl_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_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_complete_scan(priv, true);
123 }
124
125 static void iwl_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_send_scan_abort(priv);
142         if (ret) {
143                 IWL_DEBUG_SCAN(priv, "Send scan abort failed %d\n", ret);
144                 iwl_force_scan_end(priv);
145         } else
146                 IWL_DEBUG_SCAN(priv, "Sucessfully send scan abort\n");
147 }
148
149 /**
150  * iwl_scan_cancel - Cancel any currently executing HW scan
151  */
152 int iwl_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_scan_cancel);
159
160 /**
161  * iwl_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_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_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_scan_cancel_timeout);
184
185 /* Service response to REPLY_SCAN_CMD (0x80) */
186 static void iwl_rx_reply_scan(struct iwl_priv *priv,
187                               struct iwl_rx_mem_buffer *rxb)
188 {
189 #ifdef CONFIG_IWLWIFI_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_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_rx_scan_results_notif(struct iwl_priv *priv,
218                                       struct iwl_rx_mem_buffer *rxb)
219 {
220 #ifdef CONFIG_IWLWIFI_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_rx_scan_complete_notif(struct iwl_priv *priv,
240                                        struct iwl_rx_mem_buffer *rxb)
241 {
242         struct iwl_rx_packet *pkt = rxb_addr(rxb);
243         struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw;
244
245         IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
246                        scan_notif->scanned_channels,
247                        scan_notif->tsf_low,
248                        scan_notif->tsf_high, scan_notif->status);
249
250         /* The HW is no longer scanning */
251         clear_bit(STATUS_SCAN_HW, &priv->status);
252
253         IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n",
254                        (priv->scan_band == IEEE80211_BAND_2GHZ) ? "2.4" : "5.2",
255                        jiffies_to_msecs(elapsed_jiffies
256                                         (priv->scan_start, jiffies)));
257
258         queue_work(priv->workqueue, &priv->scan_completed);
259
260         if (priv->iw_mode != NL80211_IFTYPE_ADHOC &&
261             priv->cfg->bt_params &&
262             priv->cfg->bt_params->advanced_bt_coexist &&
263             priv->bt_status != scan_notif->bt_status) {
264                 if (scan_notif->bt_status) {
265                         /* BT on */
266                         if (!priv->bt_ch_announce)
267                                 priv->bt_traffic_load =
268                                         IWL_BT_COEX_TRAFFIC_LOAD_HIGH;
269                         /*
270                          * otherwise, no traffic load information provided
271                          * no changes made
272                          */
273                 } else {
274                         /* BT off */
275                         priv->bt_traffic_load =
276                                 IWL_BT_COEX_TRAFFIC_LOAD_NONE;
277                 }
278                 priv->bt_status = scan_notif->bt_status;
279                 queue_work(priv->workqueue, &priv->bt_traffic_change_work);
280         }
281 }
282
283 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
284 {
285         /* scan handlers */
286         priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
287         priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
288         priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
289                                         iwl_rx_scan_results_notif;
290         priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
291                                         iwl_rx_scan_complete_notif;
292 }
293 EXPORT_SYMBOL(iwl_setup_rx_scan_handlers);
294
295 inline u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
296                                      enum ieee80211_band band,
297                                      u8 n_probes)
298 {
299         if (band == IEEE80211_BAND_5GHZ)
300                 return IWL_ACTIVE_DWELL_TIME_52 +
301                         IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
302         else
303                 return IWL_ACTIVE_DWELL_TIME_24 +
304                         IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
305 }
306 EXPORT_SYMBOL(iwl_get_active_dwell_time);
307
308 u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
309                                enum ieee80211_band band,
310                                struct ieee80211_vif *vif)
311 {
312         struct iwl_rxon_context *ctx;
313         u16 passive = (band == IEEE80211_BAND_2GHZ) ?
314             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
315             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
316
317         if (iwl_is_any_associated(priv)) {
318                 /*
319                  * If we're associated, we clamp the maximum passive
320                  * dwell time to be 98% of the smallest beacon interval
321                  * (minus 2 * channel tune time)
322                  */
323                 for_each_context(priv, ctx) {
324                         u16 value;
325
326                         if (!iwl_is_associated_ctx(ctx))
327                                 continue;
328                         value = ctx->vif ? ctx->vif->bss_conf.beacon_int : 0;
329                         if ((value > IWL_PASSIVE_DWELL_BASE) || !value)
330                                 value = IWL_PASSIVE_DWELL_BASE;
331                         value = (value * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
332                         passive = min(value, passive);
333                 }
334         }
335
336         return passive;
337 }
338 EXPORT_SYMBOL(iwl_get_passive_dwell_time);
339
340 void iwl_init_scan_params(struct iwl_priv *priv)
341 {
342         u8 ant_idx = fls(priv->hw_params.valid_tx_ant) - 1;
343         if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ])
344                 priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx;
345         if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ])
346                 priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx;
347 }
348 EXPORT_SYMBOL(iwl_init_scan_params);
349
350 static int __must_check iwl_scan_initiate(struct iwl_priv *priv,
351                                           struct ieee80211_vif *vif,
352                                           bool internal,
353                                           enum ieee80211_band band)
354 {
355         int ret;
356
357         lockdep_assert_held(&priv->mutex);
358
359         if (WARN_ON(!priv->cfg->ops->utils->request_scan))
360                 return -EOPNOTSUPP;
361
362         cancel_delayed_work(&priv->scan_check);
363
364         if (!iwl_is_ready_rf(priv)) {
365                 IWL_WARN(priv, "Request scan called when driver not ready.\n");
366                 return -EIO;
367         }
368
369         if (test_bit(STATUS_SCAN_HW, &priv->status)) {
370                 IWL_DEBUG_SCAN(priv,
371                         "Multiple concurrent scan requests in parallel.\n");
372                 return -EBUSY;
373         }
374
375         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
376                 IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n");
377                 return -EBUSY;
378         }
379
380         IWL_DEBUG_SCAN(priv, "Starting %sscan...\n",
381                         internal ? "internal short " : "");
382
383         set_bit(STATUS_SCANNING, &priv->status);
384         priv->is_internal_short_scan = internal;
385         priv->scan_start = jiffies;
386         priv->scan_band = band;
387
388         ret = priv->cfg->ops->utils->request_scan(priv, vif);
389         if (ret) {
390                 clear_bit(STATUS_SCANNING, &priv->status);
391                 priv->is_internal_short_scan = false;
392                 return ret;
393         }
394
395         queue_delayed_work(priv->workqueue, &priv->scan_check,
396                            IWL_SCAN_CHECK_WATCHDOG);
397
398         return 0;
399 }
400
401 int iwl_mac_hw_scan(struct ieee80211_hw *hw,
402                     struct ieee80211_vif *vif,
403                     struct cfg80211_scan_request *req)
404 {
405         struct iwl_priv *priv = hw->priv;
406         int ret;
407
408         IWL_DEBUG_MAC80211(priv, "enter\n");
409
410         if (req->n_channels == 0)
411                 return -EINVAL;
412
413         mutex_lock(&priv->mutex);
414
415         if (test_bit(STATUS_SCANNING, &priv->status) &&
416             !priv->is_internal_short_scan) {
417                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
418                 ret = -EAGAIN;
419                 goto out_unlock;
420         }
421
422         /* mac80211 will only ask for one band at a time */
423         priv->scan_request = req;
424         priv->scan_vif = vif;
425
426         /*
427          * If an internal scan is in progress, just set
428          * up the scan_request as per above.
429          */
430         if (priv->is_internal_short_scan) {
431                 IWL_DEBUG_SCAN(priv, "SCAN request during internal scan\n");
432                 ret = 0;
433         } else
434                 ret = iwl_scan_initiate(priv, vif, false,
435                                         req->channels[0]->band);
436
437         IWL_DEBUG_MAC80211(priv, "leave\n");
438
439 out_unlock:
440         mutex_unlock(&priv->mutex);
441
442         return ret;
443 }
444 EXPORT_SYMBOL(iwl_mac_hw_scan);
445
446 /*
447  * internal short scan, this function should only been called while associated.
448  * It will reset and tune the radio to prevent possible RF related problem
449  */
450 void iwl_internal_short_hw_scan(struct iwl_priv *priv)
451 {
452         queue_work(priv->workqueue, &priv->start_internal_scan);
453 }
454
455 static void iwl_bg_start_internal_scan(struct work_struct *work)
456 {
457         struct iwl_priv *priv =
458                 container_of(work, struct iwl_priv, start_internal_scan);
459
460         IWL_DEBUG_SCAN(priv, "Start internal scan\n");
461
462         mutex_lock(&priv->mutex);
463
464         if (priv->is_internal_short_scan == true) {
465                 IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
466                 goto unlock;
467         }
468
469         if (test_bit(STATUS_SCANNING, &priv->status)) {
470                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
471                 goto unlock;
472         }
473
474         if (iwl_scan_initiate(priv, NULL, true, priv->band))
475                 IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n");
476  unlock:
477         mutex_unlock(&priv->mutex);
478 }
479
480 static void iwl_bg_scan_check(struct work_struct *data)
481 {
482         struct iwl_priv *priv =
483             container_of(data, struct iwl_priv, scan_check.work);
484
485         IWL_DEBUG_SCAN(priv, "Scan check work\n");
486
487         /* Since we are here firmware does not finish scan and
488          * most likely is in bad shape, so we don't bother to
489          * send abort command, just force scan complete to mac80211 */
490         mutex_lock(&priv->mutex);
491         iwl_force_scan_end(priv);
492         mutex_unlock(&priv->mutex);
493 }
494
495 /**
496  * iwl_fill_probe_req - fill in all required fields and IE for probe request
497  */
498
499 u16 iwl_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
500                        const u8 *ta, const u8 *ies, int ie_len, int left)
501 {
502         int len = 0;
503         u8 *pos = NULL;
504
505         /* Make sure there is enough space for the probe request,
506          * two mandatory IEs and the data */
507         left -= 24;
508         if (left < 0)
509                 return 0;
510
511         frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
512         memcpy(frame->da, iwl_bcast_addr, ETH_ALEN);
513         memcpy(frame->sa, ta, ETH_ALEN);
514         memcpy(frame->bssid, iwl_bcast_addr, ETH_ALEN);
515         frame->seq_ctrl = 0;
516
517         len += 24;
518
519         /* ...next IE... */
520         pos = &frame->u.probe_req.variable[0];
521
522         /* fill in our indirect SSID IE */
523         left -= 2;
524         if (left < 0)
525                 return 0;
526         *pos++ = WLAN_EID_SSID;
527         *pos++ = 0;
528
529         len += 2;
530
531         if (WARN_ON(left < ie_len))
532                 return len;
533
534         if (ies && ie_len) {
535                 memcpy(pos, ies, ie_len);
536                 len += ie_len;
537         }
538
539         return (u16)len;
540 }
541 EXPORT_SYMBOL(iwl_fill_probe_req);
542
543 static void iwl_bg_abort_scan(struct work_struct *work)
544 {
545         struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
546
547         IWL_DEBUG_SCAN(priv, "Abort scan work\n");
548
549         /* We keep scan_check work queued in case when firmware will not
550          * report back scan completed notification */
551         mutex_lock(&priv->mutex);
552         iwl_scan_cancel_timeout(priv, 200);
553         mutex_unlock(&priv->mutex);
554 }
555
556 static void iwl_bg_scan_completed(struct work_struct *work)
557 {
558         struct iwl_priv *priv =
559             container_of(work, struct iwl_priv, scan_completed);
560         bool aborted;
561
562         IWL_DEBUG_SCAN(priv, "Completed %sscan.\n",
563                        priv->is_internal_short_scan ? "internal short " : "");
564
565         cancel_delayed_work(&priv->scan_check);
566
567         mutex_lock(&priv->mutex);
568
569         aborted = test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->status);
570         if (aborted)
571                 IWL_DEBUG_SCAN(priv, "Aborted scan completed.\n");
572
573         if (!test_and_clear_bit(STATUS_SCANNING, &priv->status)) {
574                 IWL_DEBUG_SCAN(priv, "Scan already completed.\n");
575                 goto out_settings;
576         }
577
578         if (priv->is_internal_short_scan && !aborted) {
579                 int err;
580
581                 /* Check if mac80211 requested scan during our internal scan */
582                 if (priv->scan_request == NULL)
583                         goto out_complete;
584
585                 /* If so request a new scan */
586                 err = iwl_scan_initiate(priv, priv->scan_vif, false,
587                                         priv->scan_request->channels[0]->band);
588                 if (err) {
589                         IWL_DEBUG_SCAN(priv,
590                                 "failed to initiate pending scan: %d\n", err);
591                         aborted = true;
592                         goto out_complete;
593                 }
594
595                 goto out;
596         }
597
598 out_complete:
599         iwl_complete_scan(priv, aborted);
600
601 out_settings:
602         /* Can we still talk to firmware ? */
603         if (!iwl_is_ready_rf(priv))
604                 goto out;
605
606         /*
607          * We do not commit power settings while scan is pending,
608          * do it now if the settings changed.
609          */
610         iwl_set_tx_power(priv, priv->tx_power_next, false);
611
612         priv->cfg->ops->utils->post_scan(priv);
613
614 out:
615         mutex_unlock(&priv->mutex);
616 }
617
618 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
619 {
620         INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
621         INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
622         INIT_WORK(&priv->start_internal_scan, iwl_bg_start_internal_scan);
623         INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
624 }
625 EXPORT_SYMBOL(iwl_setup_scan_deferred_work);
626
627 void iwl_cancel_scan_deferred_work(struct iwl_priv *priv)
628 {
629         cancel_work_sync(&priv->start_internal_scan);
630         cancel_work_sync(&priv->abort_scan);
631         cancel_work_sync(&priv->scan_completed);
632
633         if (cancel_delayed_work_sync(&priv->scan_check)) {
634                 mutex_lock(&priv->mutex);
635                 iwl_force_scan_end(priv);
636                 mutex_unlock(&priv->mutex);
637         }
638 }
639 EXPORT_SYMBOL(iwl_cancel_scan_deferred_work);