2 * Scanning implementation
4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
5 * Copyright 2004, Instant802 Networks, Inc.
6 * Copyright 2005, Devicescape Software, Inc.
7 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
15 #include <linux/if_arp.h>
16 #include <linux/rtnetlink.h>
17 #include <linux/pm_qos_params.h>
18 #include <net/sch_generic.h>
19 #include <linux/slab.h>
20 #include <net/mac80211.h>
22 #include "ieee80211_i.h"
23 #include "driver-ops.h"
26 #define IEEE80211_PROBE_DELAY (HZ / 33)
27 #define IEEE80211_CHANNEL_TIME (HZ / 33)
28 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8)
30 struct ieee80211_bss
*
31 ieee80211_rx_bss_get(struct ieee80211_local
*local
, u8
*bssid
, int freq
,
32 u8
*ssid
, u8 ssid_len
)
34 struct cfg80211_bss
*cbss
;
36 cbss
= cfg80211_get_bss(local
->hw
.wiphy
,
37 ieee80211_get_channel(local
->hw
.wiphy
, freq
),
38 bssid
, ssid
, ssid_len
, 0, 0);
41 return (void *)cbss
->priv
;
44 static void ieee80211_rx_bss_free(struct cfg80211_bss
*cbss
)
46 struct ieee80211_bss
*bss
= (void *)cbss
->priv
;
48 kfree(bss_mesh_id(bss
));
49 kfree(bss_mesh_cfg(bss
));
52 void ieee80211_rx_bss_put(struct ieee80211_local
*local
,
53 struct ieee80211_bss
*bss
)
57 cfg80211_put_bss(container_of((void *)bss
, struct cfg80211_bss
, priv
));
60 static bool is_uapsd_supported(struct ieee802_11_elems
*elems
)
64 if (elems
->wmm_info
&& elems
->wmm_info_len
== 7
65 && elems
->wmm_info
[5] == 1)
66 qos_info
= elems
->wmm_info
[6];
67 else if (elems
->wmm_param
&& elems
->wmm_param_len
== 24
68 && elems
->wmm_param
[5] == 1)
69 qos_info
= elems
->wmm_param
[6];
71 /* no valid wmm information or parameter element found */
74 return qos_info
& IEEE80211_WMM_IE_AP_QOSINFO_UAPSD
;
77 struct ieee80211_bss
*
78 ieee80211_bss_info_update(struct ieee80211_local
*local
,
79 struct ieee80211_rx_status
*rx_status
,
80 struct ieee80211_mgmt
*mgmt
,
82 struct ieee802_11_elems
*elems
,
83 struct ieee80211_channel
*channel
,
86 struct cfg80211_bss
*cbss
;
87 struct ieee80211_bss
*bss
;
91 if (local
->hw
.flags
& IEEE80211_HW_SIGNAL_DBM
)
92 signal
= rx_status
->signal
* 100;
93 else if (local
->hw
.flags
& IEEE80211_HW_SIGNAL_UNSPEC
)
94 signal
= (rx_status
->signal
* 100) / local
->hw
.max_signal
;
96 cbss
= cfg80211_inform_bss_frame(local
->hw
.wiphy
, channel
,
97 mgmt
, len
, signal
, GFP_ATOMIC
);
102 cbss
->free_priv
= ieee80211_rx_bss_free
;
103 bss
= (void *)cbss
->priv
;
105 /* save the ERP value so that it is available at association time */
106 if (elems
->erp_info
&& elems
->erp_info_len
>= 1) {
107 bss
->erp_value
= elems
->erp_info
[0];
108 bss
->has_erp_value
= 1;
112 struct ieee80211_tim_ie
*tim_ie
=
113 (struct ieee80211_tim_ie
*)elems
->tim
;
114 bss
->dtim_period
= tim_ie
->dtim_period
;
117 /* If the beacon had no TIM IE, or it was invalid, use 1 */
118 if (beacon
&& !bss
->dtim_period
)
119 bss
->dtim_period
= 1;
121 /* replace old supported rates if we get new values */
123 if (elems
->supp_rates
) {
124 clen
= IEEE80211_MAX_SUPP_RATES
;
125 if (clen
> elems
->supp_rates_len
)
126 clen
= elems
->supp_rates_len
;
127 memcpy(bss
->supp_rates
, elems
->supp_rates
, clen
);
130 if (elems
->ext_supp_rates
) {
131 clen
= IEEE80211_MAX_SUPP_RATES
- srlen
;
132 if (clen
> elems
->ext_supp_rates_len
)
133 clen
= elems
->ext_supp_rates_len
;
134 memcpy(bss
->supp_rates
+ srlen
, elems
->ext_supp_rates
, clen
);
138 bss
->supp_rates_len
= srlen
;
140 bss
->wmm_used
= elems
->wmm_param
|| elems
->wmm_info
;
141 bss
->uapsd_supported
= is_uapsd_supported(elems
);
144 bss
->last_probe_resp
= jiffies
;
150 ieee80211_scan_rx(struct ieee80211_sub_if_data
*sdata
, struct sk_buff
*skb
)
152 struct ieee80211_rx_status
*rx_status
= IEEE80211_SKB_RXCB(skb
);
153 struct ieee80211_mgmt
*mgmt
;
154 struct ieee80211_bss
*bss
;
156 struct ieee80211_channel
*channel
;
160 bool presp
, beacon
= false;
161 struct ieee802_11_elems elems
;
164 return RX_DROP_UNUSABLE
;
166 mgmt
= (struct ieee80211_mgmt
*) skb
->data
;
167 fc
= mgmt
->frame_control
;
169 if (ieee80211_is_ctl(fc
))
173 return RX_DROP_MONITOR
;
175 presp
= ieee80211_is_probe_resp(fc
);
177 /* ignore ProbeResp to foreign address */
178 if (memcmp(mgmt
->da
, sdata
->vif
.addr
, ETH_ALEN
))
179 return RX_DROP_MONITOR
;
182 elements
= mgmt
->u
.probe_resp
.variable
;
183 baselen
= offsetof(struct ieee80211_mgmt
, u
.probe_resp
.variable
);
185 beacon
= ieee80211_is_beacon(fc
);
186 baselen
= offsetof(struct ieee80211_mgmt
, u
.beacon
.variable
);
187 elements
= mgmt
->u
.beacon
.variable
;
190 if (!presp
&& !beacon
)
193 if (baselen
> skb
->len
)
194 return RX_DROP_MONITOR
;
196 ieee802_11_parse_elems(elements
, skb
->len
- baselen
, &elems
);
198 if (elems
.ds_params
&& elems
.ds_params_len
== 1)
199 freq
= ieee80211_channel_to_frequency(elems
.ds_params
[0]);
201 freq
= rx_status
->freq
;
203 channel
= ieee80211_get_channel(sdata
->local
->hw
.wiphy
, freq
);
205 if (!channel
|| channel
->flags
& IEEE80211_CHAN_DISABLED
)
206 return RX_DROP_MONITOR
;
208 bss
= ieee80211_bss_info_update(sdata
->local
, rx_status
,
209 mgmt
, skb
->len
, &elems
,
212 ieee80211_rx_bss_put(sdata
->local
, bss
);
218 /* return false if no more work */
219 static bool ieee80211_prep_hw_scan(struct ieee80211_local
*local
)
221 struct cfg80211_scan_request
*req
= local
->scan_req
;
222 enum ieee80211_band band
;
223 int i
, ielen
, n_chans
;
226 if (local
->hw_scan_band
== IEEE80211_NUM_BANDS
)
229 band
= local
->hw_scan_band
;
231 for (i
= 0; i
< req
->n_channels
; i
++) {
232 if (req
->channels
[i
]->band
== band
) {
233 local
->hw_scan_req
->channels
[n_chans
] =
239 local
->hw_scan_band
++;
242 local
->hw_scan_req
->n_channels
= n_chans
;
244 ielen
= ieee80211_build_preq_ies(local
, (u8
*)local
->hw_scan_req
->ie
,
245 req
->ie
, req
->ie_len
, band
);
246 local
->hw_scan_req
->ie_len
= ielen
;
251 void ieee80211_scan_completed(struct ieee80211_hw
*hw
, bool aborted
)
253 struct ieee80211_local
*local
= hw_to_local(hw
);
256 trace_api_scan_completed(local
, aborted
);
258 mutex_lock(&local
->scan_mtx
);
261 * It's ok to abort a not-yet-running scan (that
262 * we have one at all will be verified by checking
263 * local->scan_req next), but not to complete it
266 if (WARN_ON(!local
->scanning
&& !aborted
))
269 if (WARN_ON(!local
->scan_req
)) {
270 mutex_unlock(&local
->scan_mtx
);
274 was_hw_scan
= test_bit(SCAN_HW_SCANNING
, &local
->scanning
);
275 if (was_hw_scan
&& !aborted
&& ieee80211_prep_hw_scan(local
)) {
276 ieee80211_queue_delayed_work(&local
->hw
,
277 &local
->scan_work
, 0);
278 mutex_unlock(&local
->scan_mtx
);
282 kfree(local
->hw_scan_req
);
283 local
->hw_scan_req
= NULL
;
285 if (local
->scan_req
!= local
->int_scan_req
)
286 cfg80211_scan_done(local
->scan_req
, aborted
);
287 local
->scan_req
= NULL
;
288 local
->scan_sdata
= NULL
;
291 local
->scan_channel
= NULL
;
293 /* we only have to protect scan_req and hw/sw scan */
294 mutex_unlock(&local
->scan_mtx
);
296 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
);
300 ieee80211_configure_filter(local
);
302 drv_sw_scan_complete(local
);
304 ieee80211_offchannel_return(local
, true);
307 ieee80211_recalc_idle(local
);
308 ieee80211_mlme_notify_scan_completed(local
);
309 ieee80211_ibss_notify_scan_completed(local
);
310 ieee80211_mesh_notify_scan_completed(local
);
311 ieee80211_queue_work(&local
->hw
, &local
->work_work
);
313 EXPORT_SYMBOL(ieee80211_scan_completed
);
315 static int ieee80211_start_sw_scan(struct ieee80211_local
*local
)
318 * Hardware/driver doesn't support hw_scan, so use software
319 * scanning instead. First send a nullfunc frame with power save
320 * bit on so that AP will buffer the frames for us while we are not
321 * listening, then send probe requests to each channel and wait for
322 * the responses. After all channels are scanned, tune back to the
323 * original channel and send a nullfunc frame with power save bit
324 * off to trigger the AP to send us all the buffered frames.
326 * Note that while local->sw_scanning is true everything else but
327 * nullfunc frames and probe requests will be dropped in
328 * ieee80211_tx_h_check_assoc().
330 drv_sw_scan_start(local
);
332 ieee80211_offchannel_stop_beaconing(local
);
334 local
->leave_oper_channel_time
= 0;
335 local
->next_scan_state
= SCAN_DECISION
;
336 local
->scan_channel_idx
= 0;
338 drv_flush(local
, false);
340 ieee80211_configure_filter(local
);
342 ieee80211_queue_delayed_work(&local
->hw
,
344 IEEE80211_CHANNEL_TIME
);
350 static int __ieee80211_start_scan(struct ieee80211_sub_if_data
*sdata
,
351 struct cfg80211_scan_request
*req
)
353 struct ieee80211_local
*local
= sdata
->local
;
359 if (!list_empty(&local
->work_list
)) {
360 /* wait for the work to finish/time out */
361 local
->scan_req
= req
;
362 local
->scan_sdata
= sdata
;
366 if (local
->ops
->hw_scan
) {
369 local
->hw_scan_req
= kmalloc(
370 sizeof(*local
->hw_scan_req
) +
371 req
->n_channels
* sizeof(req
->channels
[0]) +
372 2 + IEEE80211_MAX_SSID_LEN
+ local
->scan_ies_len
+
373 req
->ie_len
, GFP_KERNEL
);
374 if (!local
->hw_scan_req
)
377 local
->hw_scan_req
->ssids
= req
->ssids
;
378 local
->hw_scan_req
->n_ssids
= req
->n_ssids
;
379 ies
= (u8
*)local
->hw_scan_req
+
380 sizeof(*local
->hw_scan_req
) +
381 req
->n_channels
* sizeof(req
->channels
[0]);
382 local
->hw_scan_req
->ie
= ies
;
384 local
->hw_scan_band
= 0;
387 * After allocating local->hw_scan_req, we must
388 * go through until ieee80211_prep_hw_scan(), so
389 * anything that might be changed here and leave
390 * this function early must not go after this
395 local
->scan_req
= req
;
396 local
->scan_sdata
= sdata
;
398 if (local
->ops
->hw_scan
)
399 __set_bit(SCAN_HW_SCANNING
, &local
->scanning
);
401 __set_bit(SCAN_SW_SCANNING
, &local
->scanning
);
404 * Kicking off the scan need not be protected,
405 * only the scan variable stuff, since now
406 * local->scan_req is assigned and other callers
407 * will abort their scan attempts.
409 * This avoids too many locking dependencies
410 * so that the scan completed calls have more
414 ieee80211_recalc_idle(local
);
415 mutex_unlock(&local
->scan_mtx
);
417 if (local
->ops
->hw_scan
) {
418 WARN_ON(!ieee80211_prep_hw_scan(local
));
419 rc
= drv_hw_scan(local
, sdata
, local
->hw_scan_req
);
421 rc
= ieee80211_start_sw_scan(local
);
423 mutex_lock(&local
->scan_mtx
);
426 kfree(local
->hw_scan_req
);
427 local
->hw_scan_req
= NULL
;
430 ieee80211_recalc_idle(local
);
432 local
->scan_req
= NULL
;
433 local
->scan_sdata
= NULL
;
440 ieee80211_scan_get_channel_time(struct ieee80211_channel
*chan
)
443 * TODO: channel switching also consumes quite some time,
444 * add that delay as well to get a better estimation
446 if (chan
->flags
& IEEE80211_CHAN_PASSIVE_SCAN
)
447 return IEEE80211_PASSIVE_CHANNEL_TIME
;
448 return IEEE80211_PROBE_DELAY
+ IEEE80211_CHANNEL_TIME
;
451 static int ieee80211_scan_state_decision(struct ieee80211_local
*local
,
452 unsigned long *next_delay
)
454 bool associated
= false;
455 bool tx_empty
= true;
457 bool listen_int_exceeded
;
458 unsigned long min_beacon_int
= 0;
459 struct ieee80211_sub_if_data
*sdata
;
460 struct ieee80211_channel
*next_chan
;
462 /* if no more bands/channels left, complete scan and advance to the idle state */
463 if (local
->scan_channel_idx
>= local
->scan_req
->n_channels
) {
464 ieee80211_scan_completed(&local
->hw
, false);
469 * check if at least one STA interface is associated,
470 * check if at least one STA interface has pending tx frames
471 * and grab the lowest used beacon interval
473 mutex_lock(&local
->iflist_mtx
);
474 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
475 if (!ieee80211_sdata_running(sdata
))
478 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
479 if (sdata
->u
.mgd
.associated
) {
482 if (sdata
->vif
.bss_conf
.beacon_int
<
483 min_beacon_int
|| min_beacon_int
== 0)
485 sdata
->vif
.bss_conf
.beacon_int
;
487 if (!qdisc_all_tx_empty(sdata
->dev
)) {
494 mutex_unlock(&local
->iflist_mtx
);
496 if (local
->scan_channel
) {
498 * we're currently scanning a different channel, let's
499 * see if we can scan another channel without interfering
500 * with the current traffic situation.
502 * Since we don't know if the AP has pending frames for us
503 * we can only check for our tx queues and use the current
504 * pm_qos requirements for rx. Hence, if no tx traffic occurs
505 * at all we will scan as many channels in a row as the pm_qos
506 * latency allows us to. Additionally we also check for the
507 * currently negotiated listen interval to prevent losing
508 * frames unnecessarily.
510 * Otherwise switch back to the operating channel.
512 next_chan
= local
->scan_req
->channels
[local
->scan_channel_idx
];
514 bad_latency
= time_after(jiffies
+
515 ieee80211_scan_get_channel_time(next_chan
),
516 local
->leave_oper_channel_time
+
517 usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY
)));
519 listen_int_exceeded
= time_after(jiffies
+
520 ieee80211_scan_get_channel_time(next_chan
),
521 local
->leave_oper_channel_time
+
522 usecs_to_jiffies(min_beacon_int
* 1024) *
523 local
->hw
.conf
.listen_interval
);
525 if (associated
&& ( !tx_empty
|| bad_latency
||
526 listen_int_exceeded
))
527 local
->next_scan_state
= SCAN_ENTER_OPER_CHANNEL
;
529 local
->next_scan_state
= SCAN_SET_CHANNEL
;
532 * we're on the operating channel currently, let's
533 * leave that channel now to scan another one
535 local
->next_scan_state
= SCAN_LEAVE_OPER_CHANNEL
;
542 static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local
*local
,
543 unsigned long *next_delay
)
545 ieee80211_offchannel_stop_station(local
);
547 __set_bit(SCAN_OFF_CHANNEL
, &local
->scanning
);
550 * What if the nullfunc frames didn't arrive?
552 drv_flush(local
, false);
553 if (local
->ops
->flush
)
556 *next_delay
= HZ
/ 10;
558 /* remember when we left the operating channel */
559 local
->leave_oper_channel_time
= jiffies
;
561 /* advance to the next channel to be scanned */
562 local
->next_scan_state
= SCAN_SET_CHANNEL
;
565 static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local
*local
,
566 unsigned long *next_delay
)
568 /* switch back to the operating channel */
569 local
->scan_channel
= NULL
;
570 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
);
573 * Only re-enable station mode interface now; beaconing will be
574 * re-enabled once the full scan has been completed.
576 ieee80211_offchannel_return(local
, false);
578 __clear_bit(SCAN_OFF_CHANNEL
, &local
->scanning
);
580 *next_delay
= HZ
/ 5;
581 local
->next_scan_state
= SCAN_DECISION
;
584 static void ieee80211_scan_state_set_channel(struct ieee80211_local
*local
,
585 unsigned long *next_delay
)
588 struct ieee80211_channel
*chan
;
591 chan
= local
->scan_req
->channels
[local
->scan_channel_idx
];
593 local
->scan_channel
= chan
;
594 if (ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
))
597 /* advance state machine to next channel/band */
598 local
->scan_channel_idx
++;
601 /* if we skip this channel return to the decision state */
602 local
->next_scan_state
= SCAN_DECISION
;
607 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
608 * (which unfortunately doesn't say _why_ step a) is done,
609 * but it waits for the probe delay or until a frame is
610 * received - and the received frame would update the NAV).
611 * For now, we do not support waiting until a frame is
614 * In any case, it is not necessary for a passive scan.
616 if (chan
->flags
& IEEE80211_CHAN_PASSIVE_SCAN
||
617 !local
->scan_req
->n_ssids
) {
618 *next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
619 local
->next_scan_state
= SCAN_DECISION
;
623 /* active scan, send probes */
624 *next_delay
= IEEE80211_PROBE_DELAY
;
625 local
->next_scan_state
= SCAN_SEND_PROBE
;
628 static void ieee80211_scan_state_send_probe(struct ieee80211_local
*local
,
629 unsigned long *next_delay
)
632 struct ieee80211_sub_if_data
*sdata
= local
->scan_sdata
;
634 for (i
= 0; i
< local
->scan_req
->n_ssids
; i
++)
635 ieee80211_send_probe_req(
637 local
->scan_req
->ssids
[i
].ssid
,
638 local
->scan_req
->ssids
[i
].ssid_len
,
639 local
->scan_req
->ie
, local
->scan_req
->ie_len
);
642 * After sending probe requests, wait for probe responses
645 *next_delay
= IEEE80211_CHANNEL_TIME
;
646 local
->next_scan_state
= SCAN_DECISION
;
649 void ieee80211_scan_work(struct work_struct
*work
)
651 struct ieee80211_local
*local
=
652 container_of(work
, struct ieee80211_local
, scan_work
.work
);
653 struct ieee80211_sub_if_data
*sdata
= local
->scan_sdata
;
654 unsigned long next_delay
= 0;
656 mutex_lock(&local
->scan_mtx
);
657 if (!sdata
|| !local
->scan_req
) {
658 mutex_unlock(&local
->scan_mtx
);
662 if (local
->hw_scan_req
) {
663 int rc
= drv_hw_scan(local
, sdata
, local
->hw_scan_req
);
664 mutex_unlock(&local
->scan_mtx
);
666 ieee80211_scan_completed(&local
->hw
, true);
670 if (local
->scan_req
&& !local
->scanning
) {
671 struct cfg80211_scan_request
*req
= local
->scan_req
;
674 local
->scan_req
= NULL
;
675 local
->scan_sdata
= NULL
;
677 rc
= __ieee80211_start_scan(sdata
, req
);
678 mutex_unlock(&local
->scan_mtx
);
681 ieee80211_scan_completed(&local
->hw
, true);
685 mutex_unlock(&local
->scan_mtx
);
688 * Avoid re-scheduling when the sdata is going away.
690 if (!ieee80211_sdata_running(sdata
)) {
691 ieee80211_scan_completed(&local
->hw
, true);
696 * as long as no delay is required advance immediately
697 * without scheduling a new work
700 switch (local
->next_scan_state
) {
702 if (ieee80211_scan_state_decision(local
, &next_delay
))
705 case SCAN_SET_CHANNEL
:
706 ieee80211_scan_state_set_channel(local
, &next_delay
);
708 case SCAN_SEND_PROBE
:
709 ieee80211_scan_state_send_probe(local
, &next_delay
);
711 case SCAN_LEAVE_OPER_CHANNEL
:
712 ieee80211_scan_state_leave_oper_channel(local
, &next_delay
);
714 case SCAN_ENTER_OPER_CHANNEL
:
715 ieee80211_scan_state_enter_oper_channel(local
, &next_delay
);
718 } while (next_delay
== 0);
720 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, next_delay
);
723 int ieee80211_request_scan(struct ieee80211_sub_if_data
*sdata
,
724 struct cfg80211_scan_request
*req
)
728 mutex_lock(&sdata
->local
->scan_mtx
);
729 res
= __ieee80211_start_scan(sdata
, req
);
730 mutex_unlock(&sdata
->local
->scan_mtx
);
735 int ieee80211_request_internal_scan(struct ieee80211_sub_if_data
*sdata
,
736 const u8
*ssid
, u8 ssid_len
,
737 struct ieee80211_channel
*chan
)
739 struct ieee80211_local
*local
= sdata
->local
;
741 enum ieee80211_band band
;
743 mutex_lock(&local
->scan_mtx
);
749 /* fill internal scan request */
753 for (band
= 0; band
< IEEE80211_NUM_BANDS
; band
++) {
754 if (!local
->hw
.wiphy
->bands
[band
])
757 i
< local
->hw
.wiphy
->bands
[band
]->n_channels
;
759 local
->int_scan_req
->channels
[nchan
] =
760 &local
->hw
.wiphy
->bands
[band
]->channels
[i
];
765 local
->int_scan_req
->n_channels
= nchan
;
767 local
->int_scan_req
->channels
[0] = chan
;
768 local
->int_scan_req
->n_channels
= 1;
771 local
->int_scan_req
->ssids
= &local
->scan_ssid
;
772 local
->int_scan_req
->n_ssids
= 1;
773 memcpy(local
->int_scan_req
->ssids
[0].ssid
, ssid
, IEEE80211_MAX_SSID_LEN
);
774 local
->int_scan_req
->ssids
[0].ssid_len
= ssid_len
;
776 ret
= __ieee80211_start_scan(sdata
, sdata
->local
->int_scan_req
);
778 mutex_unlock(&local
->scan_mtx
);
782 void ieee80211_scan_cancel(struct ieee80211_local
*local
)
786 cancel_delayed_work_sync(&local
->scan_work
);
789 * Only call this function when a scan can't be
790 * queued -- mostly at suspend under RTNL.
792 mutex_lock(&local
->scan_mtx
);
793 abortscan
= test_bit(SCAN_SW_SCANNING
, &local
->scanning
) ||
794 (!local
->scanning
&& local
->scan_req
);
795 mutex_unlock(&local
->scan_mtx
);
798 ieee80211_scan_completed(&local
->hw
, true);