summaryrefslogtreecommitdiff
path: root/drivers/net/wireless/intel/iwlwifi/mvm/time-event.c
blob: e25cda9fbf6c34d951b7441b40574bfb9c0a67b7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
/******************************************************************************
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
 * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
 * Copyright(c) 2017 Intel Deutschland GmbH
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
 * USA
 *
 * The full GNU General Public License is included in this distribution
 * in the file called COPYING.
 *
 * Contact Information:
 *  Intel Linux Wireless <linuxwifi@intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 * BSD LICENSE
 *
 * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
 * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
 * Copyright(c) 2017 Intel Deutschland GmbH
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  * Neither the name Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *****************************************************************************/

#include <linux/jiffies.h>
#include <net/mac80211.h>

#include "fw/notif-wait.h"
#include "iwl-trans.h"
#include "fw-api.h"
#include "time-event.h"
#include "mvm.h"
#include "iwl-io.h"
#include "iwl-prph.h"

/*
 * For the high priority TE use a time event type that has similar priority to
 * the FW's action scan priority.
 */
#define IWL_MVM_ROC_TE_TYPE_NORMAL TE_P2P_DEVICE_DISCOVERABLE
#define IWL_MVM_ROC_TE_TYPE_MGMT_TX TE_P2P_CLIENT_ASSOC

void iwl_mvm_te_clear_data(struct iwl_mvm *mvm,
			   struct iwl_mvm_time_event_data *te_data)
{
	lockdep_assert_held(&mvm->time_event_lock);

	if (!te_data->vif)
		return;

	list_del(&te_data->list);
	te_data->running = false;
	te_data->uid = 0;
	te_data->id = TE_MAX;
	te_data->vif = NULL;
}

void iwl_mvm_roc_done_wk(struct work_struct *wk)
{
	struct iwl_mvm *mvm = container_of(wk, struct iwl_mvm, roc_done_wk);
	u32 queues = 0;

	/*
	 * Clear the ROC_RUNNING /ROC_AUX_RUNNING status bit.
	 * This will cause the TX path to drop offchannel transmissions.
	 * That would also be done by mac80211, but it is racy, in particular
	 * in the case that the time event actually completed in the firmware
	 * (which is handled in iwl_mvm_te_handle_notif).
	 */
	if (test_and_clear_bit(IWL_MVM_STATUS_ROC_RUNNING, &mvm->status)) {
		queues |= BIT(IWL_MVM_OFFCHANNEL_QUEUE);
		iwl_mvm_unref(mvm, IWL_MVM_REF_ROC);
	}
	if (test_and_clear_bit(IWL_MVM_STATUS_ROC_AUX_RUNNING, &mvm->status)) {
		queues |= BIT(mvm->aux_queue);
		iwl_mvm_unref(mvm, IWL_MVM_REF_ROC_AUX);
	}

	synchronize_net();

	/*
	 * Flush the offchannel queue -- this is called when the time
	 * event finishes or is canceled, so that frames queued for it
	 * won't get stuck on the queue and be transmitted in the next
	 * time event.
	 * We have to send the command asynchronously since this cannot
	 * be under the mutex for locking reasons, but that's not an
	 * issue as it will have to complete before the next command is
	 * executed, and a new time event means a new command.
	 */
	iwl_mvm_flush_sta(mvm, &mvm->aux_sta, true, CMD_ASYNC);

	/* Do the same for the P2P device queue (STA) */
	if (test_and_clear_bit(IWL_MVM_STATUS_NEED_FLUSH_P2P, &mvm->status)) {
		struct iwl_mvm_vif *mvmvif;

		/*
		 * NB: access to this pointer would be racy, but the flush bit
		 * can only be set when we had a P2P-Device VIF, and we have a
		 * flush of this work in iwl_mvm_prepare_mac_removal() so it's
		 * not really racy.
		 */

		if (!WARN_ON(!mvm->p2p_device_vif)) {
			mvmvif = iwl_mvm_vif_from_mac80211(mvm->p2p_device_vif);
			iwl_mvm_flush_sta(mvm, &mvmvif->bcast_sta, true,
					  CMD_ASYNC);
		}
	}
}

static void iwl_mvm_roc_finished(struct iwl_mvm *mvm)
{
	/*
	 * Of course, our status bit is just as racy as mac80211, so in
	 * addition, fire off the work struct which will drop all frames
	 * from the hardware queues that made it through the race. First
	 * it will of course synchronize the TX path to make sure that
	 * any *new* TX will be rejected.
	 */
	schedule_work(&mvm->roc_done_wk);
}

static void iwl_mvm_csa_noa_start(struct iwl_mvm *mvm)
{
	struct ieee80211_vif *csa_vif;

	rcu_read_lock();

	csa_vif = rcu_dereference(mvm->csa_vif);
	if (!csa_vif || !csa_vif->csa_active)
		goto out_unlock;

	IWL_DEBUG_TE(mvm, "CSA NOA started\n");

	/*
	 * CSA NoA is started but we still have beacons to
	 * transmit on the current channel.
	 * So we just do nothing here and the switch
	 * will be performed on the last TBTT.
	 */
	if (!ieee80211_csa_is_complete(csa_vif)) {
		IWL_WARN(mvm, "CSA NOA started too early\n");
		goto out_unlock;
	}

	ieee80211_csa_finish(csa_vif);

	rcu_read_unlock();

	RCU_INIT_POINTER(mvm->csa_vif, NULL);

	return;

out_unlock:
	rcu_read_unlock();
}

static bool iwl_mvm_te_check_disconnect(struct iwl_mvm *mvm,
					struct ieee80211_vif *vif,
					const char *errmsg)
{
	if (vif->type != NL80211_IFTYPE_STATION)
		return false;
	if (vif->bss_conf.assoc && vif->bss_conf.dtim_period)
		return false;
	if (errmsg)
		IWL_ERR(mvm, "%s\n", errmsg);

	iwl_mvm_connection_loss(mvm, vif, errmsg);
	return true;
}

static void
iwl_mvm_te_handle_notify_csa(struct iwl_mvm *mvm,
			     struct iwl_mvm_time_event_data *te_data,
			     struct iwl_time_event_notif *notif)
{
	struct ieee80211_vif *vif = te_data->vif;
	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);

	if (!notif->status)
		IWL_DEBUG_TE(mvm, "CSA time event failed to start\n");

	switch (te_data->vif->type) {
	case NL80211_IFTYPE_AP:
		if (!notif->status)
			mvmvif->csa_failed = true;
		iwl_mvm_csa_noa_start(mvm);
		break;
	case NL80211_IFTYPE_STATION:
		if (!notif->status) {
			iwl_mvm_connection_loss(mvm, vif,
						"CSA TE failed to start");
			break;
		}
		iwl_mvm_csa_client_absent(mvm, te_data->vif);
		ieee80211_chswitch_done(te_data->vif, true);
		break;
	default:
		/* should never happen */
		WARN_ON_ONCE(1);
		break;
	}

	/* we don't need it anymore */
	iwl_mvm_te_clear_data(mvm, te_data);
}

static void iwl_mvm_te_check_trigger(struct iwl_mvm *mvm,
				     struct iwl_time_event_notif *notif,
				     struct iwl_mvm_time_event_data *te_data)
{
	struct iwl_fw_dbg_trigger_tlv *trig;
	struct iwl_fw_dbg_trigger_time_event *te_trig;
	int i;

	if (!iwl_fw_dbg_trigger_enabled(mvm->fw, FW_DBG_TRIGGER_TIME_EVENT))
		return;

	trig = iwl_fw_dbg_get_trigger(mvm->fw, FW_DBG_TRIGGER_TIME_EVENT);
	te_trig = (void *)trig->data;

	if (!iwl_fw_dbg_trigger_check_stop(&mvm->fwrt,
					   ieee80211_vif_to_wdev(te_data->vif),
					   trig))
		return;

	for (i = 0; i < ARRAY_SIZE(te_trig->time_events); i++) {
		u32 trig_te_id = le32_to_cpu(te_trig->time_events[i].id);
		u32 trig_action_bitmap =
			le32_to_cpu(te_trig->time_events[i].action_bitmap);
		u32 trig_status_bitmap =
			le32_to_cpu(te_trig->time_events[i].status_bitmap);

		if (trig_te_id != te_data->id ||
		    !(trig_action_bitmap & le32_to_cpu(notif->action)) ||
		    !(trig_status_bitmap & BIT(le32_to_cpu(notif->status))))
			continue;

		iwl_fw_dbg_collect_trig(&mvm->fwrt, trig,
					"Time event %d Action 0x%x received status: %d",
					te_data->id,
					le32_to_cpu(notif->action),
					le32_to_cpu(notif->status));
		break;
	}
}

/*
 * Handles a FW notification for an event that is known to the driver.
 *
 * @mvm: the mvm component
 * @te_data: the time event data
 * @notif: the notification data corresponding the time event data.
 */
static void iwl_mvm_te_handle_notif(struct iwl_mvm *mvm,
				    struct iwl_mvm_time_event_data *te_data,
				    struct iwl_time_event_notif *notif)
{
	lockdep_assert_held(&mvm->time_event_lock);

	IWL_DEBUG_TE(mvm, "Handle time event notif - UID = 0x%x action %d\n",
		     le32_to_cpu(notif->unique_id),
		     le32_to_cpu(notif->action));

	iwl_mvm_te_check_trigger(mvm, notif, te_data);

	/*
	 * The FW sends the start/end time event notifications even for events
	 * that it fails to schedule. This is indicated in the status field of
	 * the notification. This happens in cases that the scheduler cannot
	 * find a schedule that can handle the event (for example requesting a
	 * P2P Device discoveribility, while there are other higher priority
	 * events in the system).
	 */
	if (!le32_to_cpu(notif->status)) {
		const char *msg;

		if (notif->action & cpu_to_le32(TE_V2_NOTIF_HOST_EVENT_START))
			msg = "Time Event start notification failure";
		else
			msg = "Time Event end notification failure";

		IWL_DEBUG_TE(mvm, "%s\n", msg);

		if (iwl_mvm_te_check_disconnect(mvm, te_data->vif, msg)) {
			iwl_mvm_te_clear_data(mvm, te_data);
			return;
		}
	}

	if (le32_to_cpu(notif->action) & TE_V2_NOTIF_HOST_EVENT_END) {
		IWL_DEBUG_TE(mvm,
			     "TE ended - current time %lu, estimated end %lu\n",
			     jiffies, te_data->end_jiffies);

		switch (te_data->vif->type) {
		case NL80211_IFTYPE_P2P_DEVICE:
			ieee80211_remain_on_channel_expired(mvm->hw);
			iwl_mvm_roc_finished(mvm);
			break;
		case NL80211_IFTYPE_STATION:
			/*
			 * By now, we should have finished association
			 * and know the dtim period.
			 */
			iwl_mvm_te_check_disconnect(mvm, te_data->vif,
				"No association and the time event is over already...");
			break;
		default:
			break;
		}

		iwl_mvm_te_clear_data(mvm, te_data);
	} else if (le32_to_cpu(notif->action) & TE_V2_NOTIF_HOST_EVENT_START) {
		te_data->running = true;
		te_data->end_jiffies = TU_TO_EXP_TIME(te_data->duration);

		if (te_data->vif->type == NL80211_IFTYPE_P2P_DEVICE) {
			set_bit(IWL_MVM_STATUS_ROC_RUNNING, &mvm->status);
			iwl_mvm_ref(mvm, IWL_MVM_REF_ROC);
			ieee80211_ready_on_channel(mvm->hw);
		} else if (te_data->id == TE_CHANNEL_SWITCH_PERIOD) {
			iwl_mvm_te_handle_notify_csa(mvm, te_data, notif);
		}
	} else {
		IWL_WARN(mvm, "Got TE with unknown action\n");
	}
}

/*
 * Handle A Aux ROC time event
 */
static int iwl_mvm_aux_roc_te_handle_notif(struct iwl_mvm *mvm,
					   struct iwl_time_event_notif *notif)
{
	struct iwl_mvm_time_event_data *te_data, *tmp;
	bool aux_roc_te = false;

	list_for_each_entry_safe(te_data, tmp, &mvm->aux_roc_te_list, list) {
		if (le32_to_cpu(notif->unique_id) == te_data->uid) {
			aux_roc_te = true;
			break;
		}
	}
	if (!aux_roc_te) /* Not a Aux ROC time event */
		return -EINVAL;

	iwl_mvm_te_check_trigger(mvm, notif, te_data);

	IWL_DEBUG_TE(mvm,
		     "Aux ROC time event notification  - UID = 0x%x action %d (error = %d)\n",
		     le32_to_cpu(notif->unique_id),
		     le32_to_cpu(notif->action), le32_to_cpu(notif->status));

	if (!le32_to_cpu(notif->status) ||
	    le32_to_cpu(notif->action) == TE_V2_NOTIF_HOST_EVENT_END) {
		/* End TE, notify mac80211 */
		ieee80211_remain_on_channel_expired(mvm->hw);
		iwl_mvm_roc_finished(mvm); /* flush aux queue */
		list_del(&te_data->list); /* remove from list */
		te_data->running = false;
		te_data->vif = NULL;
		te_data->uid = 0;
		te_data->id = TE_MAX;
	} else if (le32_to_cpu(notif->action) == TE_V2_NOTIF_HOST_EVENT_START) {
		set_bit(IWL_MVM_STATUS_ROC_AUX_RUNNING, &mvm->status);
		te_data->running = true;
		iwl_mvm_ref(mvm, IWL_MVM_REF_ROC_AUX);
		ieee80211_ready_on_channel(mvm->hw); /* Start TE */
	} else {
		IWL_DEBUG_TE(mvm,
			     "ERROR: Unknown Aux ROC Time Event (action = %d)\n",
			     le32_to_cpu(notif->action));
		return -EINVAL;
	}

	return 0;
}

/*
 * The Rx handler for time event notifications
 */
void iwl_mvm_rx_time_event_notif(struct iwl_mvm *mvm,
				 struct iwl_rx_cmd_buffer *rxb)
{
	struct iwl_rx_packet *pkt = rxb_addr(rxb);
	struct iwl_time_event_notif *notif = (void *)pkt->data;
	struct iwl_mvm_time_event_data *te_data, *tmp;

	IWL_DEBUG_TE(mvm, "Time event notification - UID = 0x%x action %d\n",
		     le32_to_cpu(notif->unique_id),
		     le32_to_cpu(notif->action));

	spin_lock_bh(&mvm->time_event_lock);
	/* This time event is triggered for Aux ROC request */
	if (!iwl_mvm_aux_roc_te_handle_notif(mvm, notif))
		goto unlock;

	list_for_each_entry_safe(te_data, tmp, &mvm->time_event_list, list) {
		if (le32_to_cpu(notif->unique_id) == te_data->uid)
			iwl_mvm_te_handle_notif(mvm, te_data, notif);
	}
unlock:
	spin_unlock_bh(&mvm->time_event_lock);
}

static bool iwl_mvm_te_notif(struct iwl_notif_wait_data *notif_wait,
			     struct iwl_rx_packet *pkt, void *data)
{
	struct iwl_mvm *mvm =
		container_of(notif_wait, struct iwl_mvm, notif_wait);
	struct iwl_mvm_time_event_data *te_data = data;
	struct iwl_time_event_notif *resp;
	int resp_len = iwl_rx_packet_payload_len(pkt);

	if (WARN_ON(pkt->hdr.cmd != TIME_EVENT_NOTIFICATION))
		return true;

	if (WARN_ON_ONCE(resp_len != sizeof(*resp))) {
		IWL_ERR(mvm, "Invalid TIME_EVENT_NOTIFICATION response\n");
		return true;
	}

	resp = (void *)pkt->data;

	/* te_data->uid is already set in the TIME_EVENT_CMD response */
	if (le32_to_cpu(resp->unique_id) != te_data->uid)
		return false;

	IWL_DEBUG_TE(mvm, "TIME_EVENT_NOTIFICATION response - UID = 0x%x\n",
		     te_data->uid);
	if (!resp->status)
		IWL_ERR(mvm,
			"TIME_EVENT_NOTIFICATION received but not executed\n");

	return true;
}

static bool iwl_mvm_time_event_response(struct iwl_notif_wait_data *notif_wait,
					struct iwl_rx_packet *pkt, void *data)
{
	struct iwl_mvm *mvm =
		container_of(notif_wait, struct iwl_mvm, notif_wait);
	struct iwl_mvm_time_event_data *te_data = data;
	struct iwl_time_event_resp *resp;
	int resp_len = iwl_rx_packet_payload_len(pkt);

	if (WARN_ON(pkt->hdr.cmd != TIME_EVENT_CMD))
		return true;

	if (WARN_ON_ONCE(resp_len != sizeof(*resp))) {
		IWL_ERR(mvm, "Invalid TIME_EVENT_CMD response\n");
		return true;
	}

	resp = (void *)pkt->data;

	/* we should never get a response to another TIME_EVENT_CMD here */
	if (WARN_ON_ONCE(le32_to_cpu(resp->id) != te_data->id))
		return false;

	te_data->uid = le32_to_cpu(resp->unique_id);
	IWL_DEBUG_TE(mvm, "TIME_EVENT_CMD response - UID = 0x%x\n",
		     te_data->uid);
	return true;
}

static int iwl_mvm_time_event_send_add(struct iwl_mvm *mvm,
				       struct ieee80211_vif *vif,
				       struct iwl_mvm_time_event_data *te_data,
				       struct iwl_time_event_cmd *te_cmd)
{
	static const u16 time_event_response[] = { TIME_EVENT_CMD };
	struct iwl_notification_wait wait_time_event;
	int ret;

	lockdep_assert_held(&mvm->mutex);

	IWL_DEBUG_TE(mvm, "Add new TE, duration %d TU\n",
		     le32_to_cpu(te_cmd->duration));

	spin_lock_bh(&mvm->time_event_lock);
	if (WARN_ON(te_data->id != TE_MAX)) {
		spin_unlock_bh(&mvm->time_event_lock);
		return -EIO;
	}
	te_data->vif = vif;
	te_data->duration = le32_to_cpu(te_cmd->duration);
	te_data->id = le32_to_cpu(te_cmd->id);
	list_add_tail(&te_data->list, &mvm->time_event_list);
	spin_unlock_bh(&mvm->time_event_lock);

	/*
	 * Use a notification wait, which really just processes the
	 * command response and doesn't wait for anything, in order
	 * to be able to process the response and get the UID inside
	 * the RX path. Using CMD_WANT_SKB doesn't work because it
	 * stores the buffer and then wakes up this thread, by which
	 * time another notification (that the time event started)
	 * might already be processed unsuccessfully.
	 */
	iwl_init_notification_wait(&mvm->notif_wait, &wait_time_event,
				   time_event_response,
				   ARRAY_SIZE(time_event_response),
				   iwl_mvm_time_event_response, te_data);

	ret = iwl_mvm_send_cmd_pdu(mvm, TIME_EVENT_CMD, 0,
					    sizeof(*te_cmd), te_cmd);
	if (ret) {
		IWL_ERR(mvm, "Couldn't send TIME_EVENT_CMD: %d\n", ret);
		iwl_remove_notification(&mvm->notif_wait, &wait_time_event);
		goto out_clear_te;
	}

	/* No need to wait for anything, so just pass 1 (0 isn't valid) */
	ret = iwl_wait_notification(&mvm->notif_wait, &wait_time_event, 1);
	/* should never fail */
	WARN_ON_ONCE(ret);

	if (ret) {
 out_clear_te:
		spin_lock_bh(&mvm->time_event_lock);
		iwl_mvm_te_clear_data(mvm, te_data);
		spin_unlock_bh(&mvm->time_event_lock);
	}
	return ret;
}

void iwl_mvm_protect_session(struct iwl_mvm *mvm,
			     struct ieee80211_vif *vif,
			     u32 duration, u32 min_duration,
			     u32 max_delay, bool wait_for_notif)
{
	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
	struct iwl_mvm_time_event_data *te_data = &mvmvif->time_event_data;
	const u16 te_notif_response[] = { TIME_EVENT_NOTIFICATION };
	struct iwl_notification_wait wait_te_notif;
	struct iwl_time_event_cmd time_cmd = {};

	lockdep_assert_held(&mvm->mutex);

	if (te_data->running &&
	    time_after(te_data->end_jiffies, TU_TO_EXP_TIME(min_duration))) {
		IWL_DEBUG_TE(mvm, "We have enough time in the current TE: %u\n",
			     jiffies_to_msecs(te_data->end_jiffies - jiffies));
		return;
	}

	if (te_data->running) {
		IWL_DEBUG_TE(mvm, "extend 0x%x: only %u ms left\n",
			     te_data->uid,
			     jiffies_to_msecs(te_data->end_jiffies - jiffies));
		/*
		 * we don't have enough time
		 * cancel the current TE and issue a new one
		 * Of course it would be better to remove the old one only
		 * when the new one is added, but we don't care if we are off
		 * channel for a bit. All we need to do, is not to return
		 * before we actually begin to be on the channel.
		 */
		iwl_mvm_stop_session_protection(mvm, vif);
	}

	time_cmd.action = cpu_to_le32(FW_CTXT_ACTION_ADD);
	time_cmd.id_and_color =
		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
	time_cmd.id = cpu_to_le32(TE_BSS_STA_AGGRESSIVE_ASSOC);

	time_cmd.apply_time = cpu_to_le32(0);

	time_cmd.max_frags = TE_V2_FRAG_NONE;
	time_cmd.max_delay = cpu_to_le32(max_delay);
	/* TODO: why do we need to interval = bi if it is not periodic? */
	time_cmd.interval = cpu_to_le32(1);
	time_cmd.duration = cpu_to_le32(duration);
	time_cmd.repeat = 1;
	time_cmd.policy = cpu_to_le16(TE_V2_NOTIF_HOST_EVENT_START |
				      TE_V2_NOTIF_HOST_EVENT_END |
				      T2_V2_START_IMMEDIATELY);

	if (!wait_for_notif) {
		iwl_mvm_time_event_send_add(mvm, vif, te_data, &time_cmd);
		return;
	}

	/*
	 * Create notification_wait for the TIME_EVENT_NOTIFICATION to use
	 * right after we send the time event
	 */
	iwl_init_notification_wait(&mvm->notif_wait, &wait_te_notif,
				   te_notif_response,
				   ARRAY_SIZE(te_notif_response),
				   iwl_mvm_te_notif, te_data);

	/* If TE was sent OK - wait for the notification that started */
	if (iwl_mvm_time_event_send_add(mvm, vif, te_data, &time_cmd)) {
		IWL_ERR(mvm, "Failed to add TE to protect session\n");
		iwl_remove_notification(&mvm->notif_wait, &wait_te_notif);
	} else if (iwl_wait_notification(&mvm->notif_wait, &wait_te_notif,
					 TU_TO_JIFFIES(max_delay))) {
		IWL_ERR(mvm, "Failed to protect session until TE\n");
	}
}

static bool __iwl_mvm_remove_time_event(struct iwl_mvm *mvm,
					struct iwl_mvm_time_event_data *te_data,
					u32 *uid)
{
	u32 id;

	/*
	 * It is possible that by the time we got to this point the time
	 * event was already removed.
	 */
	spin_lock_bh(&mvm->time_event_lock);

	/* Save time event uid before clearing its data */
	*uid = te_data->uid;
	id = te_data->id;

	/*
	 * The clear_data function handles time events that were already removed
	 */
	iwl_mvm_te_clear_data(mvm, te_data);
	spin_unlock_bh(&mvm->time_event_lock);

	/*
	 * It is possible that by the time we try to remove it, the time event
	 * has already ended and removed. In such a case there is no need to
	 * send a removal command.
	 */
	if (id == TE_MAX) {
		IWL_DEBUG_TE(mvm, "TE 0x%x has already ended\n", *uid);
		return false;
	}

	return true;
}

/*
 * Explicit request to remove a aux roc time event. The removal of a time
 * event needs to be synchronized with the flow of a time event's end
 * notification, which also removes the time event from the op mode
 * data structures.
 */
static void iwl_mvm_remove_aux_roc_te(struct iwl_mvm *mvm,
				      struct iwl_mvm_vif *mvmvif,
				      struct iwl_mvm_time_event_data *te_data)
{
	struct iwl_hs20_roc_req aux_cmd = {};
	u32 uid;
	int ret;

	if (!__iwl_mvm_remove_time_event(mvm, te_data, &uid))
		return;

	aux_cmd.event_unique_id = cpu_to_le32(uid);
	aux_cmd.action = cpu_to_le32(FW_CTXT_ACTION_REMOVE);
	aux_cmd.id_and_color =
		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
	IWL_DEBUG_TE(mvm, "Removing BSS AUX ROC TE 0x%x\n",
		     le32_to_cpu(aux_cmd.event_unique_id));
	ret = iwl_mvm_send_cmd_pdu(mvm, HOT_SPOT_CMD, 0,
				   sizeof(aux_cmd), &aux_cmd);

	if (WARN_ON(ret))
		return;
}

/*
 * Explicit request to remove a time event. The removal of a time event needs to
 * be synchronized with the flow of a time event's end notification, which also
 * removes the time event from the op mode data structures.
 */
void iwl_mvm_remove_time_event(struct iwl_mvm *mvm,
			       struct iwl_mvm_vif *mvmvif,
			       struct iwl_mvm_time_event_data *te_data)
{
	struct iwl_time_event_cmd time_cmd = {};
	u32 uid;
	int ret;

	if (!__iwl_mvm_remove_time_event(mvm, te_data, &uid))
		return;

	/* When we remove a TE, the UID is to be set in the id field */
	time_cmd.id = cpu_to_le32(uid);
	time_cmd.action = cpu_to_le32(FW_CTXT_ACTION_REMOVE);
	time_cmd.id_and_color =
		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));

	IWL_DEBUG_TE(mvm, "Removing TE 0x%x\n", le32_to_cpu(time_cmd.id));
	ret = iwl_mvm_send_cmd_pdu(mvm, TIME_EVENT_CMD, 0,
				   sizeof(time_cmd), &time_cmd);
	if (WARN_ON(ret))
		return;
}

void iwl_mvm_stop_session_protection(struct iwl_mvm *mvm,
				     struct ieee80211_vif *vif)
{
	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
	struct iwl_mvm_time_event_data *te_data = &mvmvif->time_event_data;
	u32 id;

	lockdep_assert_held(&mvm->mutex);

	spin_lock_bh(&mvm->time_event_lock);
	id = te_data->id;
	spin_unlock_bh(&mvm->time_event_lock);

	if (id != TE_BSS_STA_AGGRESSIVE_ASSOC) {
		IWL_DEBUG_TE(mvm,
			     "don't remove TE with id=%u (not session protection)\n",
			     id);
		return;
	}

	iwl_mvm_remove_time_event(mvm, mvmvif, te_data);
}

int iwl_mvm_start_p2p_roc(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
			  int duration, enum ieee80211_roc_type type)
{
	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
	struct iwl_mvm_time_event_data *te_data = &mvmvif->time_event_data;
	struct iwl_time_event_cmd time_cmd = {};

	lockdep_assert_held(&mvm->mutex);
	if (te_data->running) {
		IWL_WARN(mvm, "P2P_DEVICE remain on channel already running\n");
		return -EBUSY;
	}

	/*
	 * Flush the done work, just in case it's still pending, so that
	 * the work it does can complete and we can accept new frames.
	 */
	flush_work(&mvm->roc_done_wk);

	time_cmd.action = cpu_to_le32(FW_CTXT_ACTION_ADD);
	time_cmd.id_and_color =
		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));

	switch (type) {
	case IEEE80211_ROC_TYPE_NORMAL:
		time_cmd.id = cpu_to_le32(IWL_MVM_ROC_TE_TYPE_NORMAL);
		break;
	case IEEE80211_ROC_TYPE_MGMT_TX:
		time_cmd.id = cpu_to_le32(IWL_MVM_ROC_TE_TYPE_MGMT_TX);
		break;
	default:
		WARN_ONCE(1, "Got an invalid ROC type\n");
		return -EINVAL;
	}

	time_cmd.apply_time = cpu_to_le32(0);
	time_cmd.interval = cpu_to_le32(1);

	/*
	 * The P2P Device TEs can have lower priority than other events
	 * that are being scheduled by the driver/fw, and thus it might not be
	 * scheduled. To improve the chances of it being scheduled, allow them
	 * to be fragmented, and in addition allow them to be delayed.
	 */
	time_cmd.max_frags = min(MSEC_TO_TU(duration)/50, TE_V2_FRAG_ENDLESS);
	time_cmd.max_delay = cpu_to_le32(MSEC_TO_TU(duration/2));
	time_cmd.duration = cpu_to_le32(MSEC_TO_TU(duration));
	time_cmd.repeat = 1;
	time_cmd.policy = cpu_to_le16(TE_V2_NOTIF_HOST_EVENT_START |
				      TE_V2_NOTIF_HOST_EVENT_END |
				      T2_V2_START_IMMEDIATELY);

	return iwl_mvm_time_event_send_add(mvm, vif, te_data, &time_cmd);
}

static struct iwl_mvm_time_event_data *iwl_mvm_get_roc_te(struct iwl_mvm *mvm)
{
	struct iwl_mvm_time_event_data *te_data;

	lockdep_assert_held(&mvm->mutex);

	spin_lock_bh(&mvm->time_event_lock);

	/*
	 * Iterate over the list of time events and find the time event that is
	 * associated with a P2P_DEVICE interface.
	 * This assumes that a P2P_DEVICE interface can have only a single time
	 * event at any given time and this time event coresponds to a ROC
	 * request
	 */
	list_for_each_entry(te_data, &mvm->time_event_list, list) {
		if (te_data->vif->type == NL80211_IFTYPE_P2P_DEVICE)
			goto out;
	}

	/* There can only be at most one AUX ROC time event, we just use the
	 * list to simplify/unify code. Remove it if it exists.
	 */
	te_data = list_first_entry_or_null(&mvm->aux_roc_te_list,
					   struct iwl_mvm_time_event_data,
					   list);
out:
	spin_unlock_bh(&mvm->time_event_lock);
	return te_data;
}

void iwl_mvm_cleanup_roc_te(struct iwl_mvm *mvm)
{
	struct iwl_mvm_time_event_data *te_data;
	u32 uid;

	te_data = iwl_mvm_get_roc_te(mvm);
	if (te_data)
		__iwl_mvm_remove_time_event(mvm, te_data, &uid);
}

void iwl_mvm_stop_roc(struct iwl_mvm *mvm)
{
	struct iwl_mvm_vif *mvmvif;
	struct iwl_mvm_time_event_data *te_data;

	te_data = iwl_mvm_get_roc_te(mvm);
	if (!te_data) {
		IWL_WARN(mvm, "No remain on channel event\n");
		return;
	}

	mvmvif = iwl_mvm_vif_from_mac80211(te_data->vif);

	if (te_data->vif->type == NL80211_IFTYPE_P2P_DEVICE) {
		iwl_mvm_remove_time_event(mvm, mvmvif, te_data);
		set_bit(IWL_MVM_STATUS_NEED_FLUSH_P2P, &mvm->status);
	} else {
		iwl_mvm_remove_aux_roc_te(mvm, mvmvif, te_data);
	}

	iwl_mvm_roc_finished(mvm);
}

int iwl_mvm_schedule_csa_period(struct iwl_mvm *mvm,
				struct ieee80211_vif *vif,
				u32 duration, u32 apply_time)
{
	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
	struct iwl_mvm_time_event_data *te_data = &mvmvif->time_event_data;
	struct iwl_time_event_cmd time_cmd = {};

	lockdep_assert_held(&mvm->mutex);

	if (te_data->running) {
		u32 id;

		spin_lock_bh(&mvm->time_event_lock);
		id = te_data->id;
		spin_unlock_bh(&mvm->time_event_lock);

		if (id == TE_CHANNEL_SWITCH_PERIOD) {
			IWL_DEBUG_TE(mvm, "CS period is already scheduled\n");
			return -EBUSY;
		}

		/*
		 * Remove the session protection time event to allow the
		 * channel switch. If we got here, we just heard a beacon so
		 * the session protection is not needed anymore anyway.
		 */
		iwl_mvm_remove_time_event(mvm, mvmvif, te_data);
	}

	time_cmd.action = cpu_to_le32(FW_CTXT_ACTION_ADD);
	time_cmd.id_and_color =
		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
	time_cmd.id = cpu_to_le32(TE_CHANNEL_SWITCH_PERIOD);
	time_cmd.apply_time = cpu_to_le32(apply_time);
	time_cmd.max_frags = TE_V2_FRAG_NONE;
	time_cmd.duration = cpu_to_le32(duration);
	time_cmd.repeat = 1;
	time_cmd.interval = cpu_to_le32(1);
	time_cmd.policy = cpu_to_le16(TE_V2_NOTIF_HOST_EVENT_START |
				      TE_V2_ABSENCE);

	return iwl_mvm_time_event_send_add(mvm, vif, te_data, &time_cmd);
}