1 /******************************************************************************
2  *
3  * This file is provided under a dual BSD/GPLv2 license.  When using or
4  * redistributing this file, you may do so under either license.
5  *
6  * GPL LICENSE SUMMARY
7  *
8  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
9  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
10  * Copyright(c) 2017 Intel Deutschland GmbH
11  * Copyright(c) 2018 Intel Corporation
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of version 2 of the GNU General Public License as
15  * published by the Free Software Foundation.
16  *
17  * This program is distributed in the hope that it will be useful, but
18  * WITHOUT ANY WARRANTY; without even the implied warranty of
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20  * General Public License for more details.
21  *
22  * The full GNU General Public License is included in this distribution
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26  *  Intel Linux Wireless <linuxwifi@intel.com>
27  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
28  *
29  * BSD LICENSE
30  *
31  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
32  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
33  * Copyright(c) 2017 Intel Deutschland GmbH
34  * Copyright(c) 2018 Intel Corporation
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63  *****************************************************************************/
64 
65 #include <linux/jiffies.h>
66 #include <net/mac80211.h>
67 
68 #include "fw/notif-wait.h"
69 #include "iwl-trans.h"
70 #include "fw-api.h"
71 #include "time-event.h"
72 #include "mvm.h"
73 #include "iwl-io.h"
74 #include "iwl-prph.h"
75 
76 /*
77  * For the high priority TE use a time event type that has similar priority to
78  * the FW's action scan priority.
79  */
80 #define IWL_MVM_ROC_TE_TYPE_NORMAL TE_P2P_DEVICE_DISCOVERABLE
81 #define IWL_MVM_ROC_TE_TYPE_MGMT_TX TE_P2P_CLIENT_ASSOC
82 
83 void iwl_mvm_te_clear_data(struct iwl_mvm *mvm,
84 			   struct iwl_mvm_time_event_data *te_data)
85 {
86 	lockdep_assert_held(&mvm->time_event_lock);
87 
88 	if (!te_data->vif)
89 		return;
90 
91 	list_del(&te_data->list);
92 	te_data->running = false;
93 	te_data->uid = 0;
94 	te_data->id = TE_MAX;
95 	te_data->vif = NULL;
96 }
97 
98 void iwl_mvm_roc_done_wk(struct work_struct *wk)
99 {
100 	struct iwl_mvm *mvm = container_of(wk, struct iwl_mvm, roc_done_wk);
101 
102 	/*
103 	 * Clear the ROC_RUNNING /ROC_AUX_RUNNING status bit.
104 	 * This will cause the TX path to drop offchannel transmissions.
105 	 * That would also be done by mac80211, but it is racy, in particular
106 	 * in the case that the time event actually completed in the firmware
107 	 * (which is handled in iwl_mvm_te_handle_notif).
108 	 */
109 	if (test_and_clear_bit(IWL_MVM_STATUS_ROC_RUNNING, &mvm->status))
110 		iwl_mvm_unref(mvm, IWL_MVM_REF_ROC);
111 	if (test_and_clear_bit(IWL_MVM_STATUS_ROC_AUX_RUNNING, &mvm->status))
112 		iwl_mvm_unref(mvm, IWL_MVM_REF_ROC_AUX);
113 
114 	synchronize_net();
115 
116 	/*
117 	 * Flush the offchannel queue -- this is called when the time
118 	 * event finishes or is canceled, so that frames queued for it
119 	 * won't get stuck on the queue and be transmitted in the next
120 	 * time event.
121 	 * We have to send the command asynchronously since this cannot
122 	 * be under the mutex for locking reasons, but that's not an
123 	 * issue as it will have to complete before the next command is
124 	 * executed, and a new time event means a new command.
125 	 */
126 	iwl_mvm_flush_sta(mvm, &mvm->aux_sta, true, CMD_ASYNC);
127 
128 	/* Do the same for the P2P device queue (STA) */
129 	if (test_and_clear_bit(IWL_MVM_STATUS_NEED_FLUSH_P2P, &mvm->status)) {
130 		struct iwl_mvm_vif *mvmvif;
131 
132 		/*
133 		 * NB: access to this pointer would be racy, but the flush bit
134 		 * can only be set when we had a P2P-Device VIF, and we have a
135 		 * flush of this work in iwl_mvm_prepare_mac_removal() so it's
136 		 * not really racy.
137 		 */
138 
139 		if (!WARN_ON(!mvm->p2p_device_vif)) {
140 			mvmvif = iwl_mvm_vif_from_mac80211(mvm->p2p_device_vif);
141 			iwl_mvm_flush_sta(mvm, &mvmvif->bcast_sta, true,
142 					  CMD_ASYNC);
143 		}
144 	}
145 }
146 
147 static void iwl_mvm_roc_finished(struct iwl_mvm *mvm)
148 {
149 	/*
150 	 * Of course, our status bit is just as racy as mac80211, so in
151 	 * addition, fire off the work struct which will drop all frames
152 	 * from the hardware queues that made it through the race. First
153 	 * it will of course synchronize the TX path to make sure that
154 	 * any *new* TX will be rejected.
155 	 */
156 	schedule_work(&mvm->roc_done_wk);
157 }
158 
159 static void iwl_mvm_csa_noa_start(struct iwl_mvm *mvm)
160 {
161 	struct ieee80211_vif *csa_vif;
162 
163 	rcu_read_lock();
164 
165 	csa_vif = rcu_dereference(mvm->csa_vif);
166 	if (!csa_vif || !csa_vif->csa_active)
167 		goto out_unlock;
168 
169 	IWL_DEBUG_TE(mvm, "CSA NOA started\n");
170 
171 	/*
172 	 * CSA NoA is started but we still have beacons to
173 	 * transmit on the current channel.
174 	 * So we just do nothing here and the switch
175 	 * will be performed on the last TBTT.
176 	 */
177 	if (!ieee80211_csa_is_complete(csa_vif)) {
178 		IWL_WARN(mvm, "CSA NOA started too early\n");
179 		goto out_unlock;
180 	}
181 
182 	ieee80211_csa_finish(csa_vif);
183 
184 	rcu_read_unlock();
185 
186 	RCU_INIT_POINTER(mvm->csa_vif, NULL);
187 
188 	return;
189 
190 out_unlock:
191 	rcu_read_unlock();
192 }
193 
194 static bool iwl_mvm_te_check_disconnect(struct iwl_mvm *mvm,
195 					struct ieee80211_vif *vif,
196 					const char *errmsg)
197 {
198 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
199 
200 	if (vif->type != NL80211_IFTYPE_STATION)
201 		return false;
202 
203 	if (!mvmvif->csa_bcn_pending && vif->bss_conf.assoc &&
204 	    vif->bss_conf.dtim_period)
205 		return false;
206 	if (errmsg)
207 		IWL_ERR(mvm, "%s\n", errmsg);
208 
209 	iwl_mvm_connection_loss(mvm, vif, errmsg);
210 	return true;
211 }
212 
213 static void
214 iwl_mvm_te_handle_notify_csa(struct iwl_mvm *mvm,
215 			     struct iwl_mvm_time_event_data *te_data,
216 			     struct iwl_time_event_notif *notif)
217 {
218 	struct ieee80211_vif *vif = te_data->vif;
219 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
220 
221 	if (!notif->status)
222 		IWL_DEBUG_TE(mvm, "CSA time event failed to start\n");
223 
224 	switch (te_data->vif->type) {
225 	case NL80211_IFTYPE_AP:
226 		if (!notif->status)
227 			mvmvif->csa_failed = true;
228 		iwl_mvm_csa_noa_start(mvm);
229 		break;
230 	case NL80211_IFTYPE_STATION:
231 		if (!notif->status) {
232 			iwl_mvm_connection_loss(mvm, vif,
233 						"CSA TE failed to start");
234 			break;
235 		}
236 		iwl_mvm_csa_client_absent(mvm, te_data->vif);
237 		ieee80211_chswitch_done(te_data->vif, true);
238 		break;
239 	default:
240 		/* should never happen */
241 		WARN_ON_ONCE(1);
242 		break;
243 	}
244 
245 	/* we don't need it anymore */
246 	iwl_mvm_te_clear_data(mvm, te_data);
247 }
248 
249 static void iwl_mvm_te_check_trigger(struct iwl_mvm *mvm,
250 				     struct iwl_time_event_notif *notif,
251 				     struct iwl_mvm_time_event_data *te_data)
252 {
253 	struct iwl_fw_dbg_trigger_tlv *trig;
254 	struct iwl_fw_dbg_trigger_time_event *te_trig;
255 	int i;
256 
257 	trig = iwl_fw_dbg_trigger_on(&mvm->fwrt,
258 				     ieee80211_vif_to_wdev(te_data->vif),
259 				     FW_DBG_TRIGGER_TIME_EVENT);
260 	if (!trig)
261 		return;
262 
263 	te_trig = (void *)trig->data;
264 
265 	for (i = 0; i < ARRAY_SIZE(te_trig->time_events); i++) {
266 		u32 trig_te_id = le32_to_cpu(te_trig->time_events[i].id);
267 		u32 trig_action_bitmap =
268 			le32_to_cpu(te_trig->time_events[i].action_bitmap);
269 		u32 trig_status_bitmap =
270 			le32_to_cpu(te_trig->time_events[i].status_bitmap);
271 
272 		if (trig_te_id != te_data->id ||
273 		    !(trig_action_bitmap & le32_to_cpu(notif->action)) ||
274 		    !(trig_status_bitmap & BIT(le32_to_cpu(notif->status))))
275 			continue;
276 
277 		iwl_fw_dbg_collect_trig(&mvm->fwrt, trig,
278 					"Time event %d Action 0x%x received status: %d",
279 					te_data->id,
280 					le32_to_cpu(notif->action),
281 					le32_to_cpu(notif->status));
282 		break;
283 	}
284 }
285 
286 /*
287  * Handles a FW notification for an event that is known to the driver.
288  *
289  * @mvm: the mvm component
290  * @te_data: the time event data
291  * @notif: the notification data corresponding the time event data.
292  */
293 static void iwl_mvm_te_handle_notif(struct iwl_mvm *mvm,
294 				    struct iwl_mvm_time_event_data *te_data,
295 				    struct iwl_time_event_notif *notif)
296 {
297 	lockdep_assert_held(&mvm->time_event_lock);
298 
299 	IWL_DEBUG_TE(mvm, "Handle time event notif - UID = 0x%x action %d\n",
300 		     le32_to_cpu(notif->unique_id),
301 		     le32_to_cpu(notif->action));
302 
303 	iwl_mvm_te_check_trigger(mvm, notif, te_data);
304 
305 	/*
306 	 * The FW sends the start/end time event notifications even for events
307 	 * that it fails to schedule. This is indicated in the status field of
308 	 * the notification. This happens in cases that the scheduler cannot
309 	 * find a schedule that can handle the event (for example requesting a
310 	 * P2P Device discoveribility, while there are other higher priority
311 	 * events in the system).
312 	 */
313 	if (!le32_to_cpu(notif->status)) {
314 		const char *msg;
315 
316 		if (notif->action & cpu_to_le32(TE_V2_NOTIF_HOST_EVENT_START))
317 			msg = "Time Event start notification failure";
318 		else
319 			msg = "Time Event end notification failure";
320 
321 		IWL_DEBUG_TE(mvm, "%s\n", msg);
322 
323 		if (iwl_mvm_te_check_disconnect(mvm, te_data->vif, msg)) {
324 			iwl_mvm_te_clear_data(mvm, te_data);
325 			return;
326 		}
327 	}
328 
329 	if (le32_to_cpu(notif->action) & TE_V2_NOTIF_HOST_EVENT_END) {
330 		IWL_DEBUG_TE(mvm,
331 			     "TE ended - current time %lu, estimated end %lu\n",
332 			     jiffies, te_data->end_jiffies);
333 
334 		switch (te_data->vif->type) {
335 		case NL80211_IFTYPE_P2P_DEVICE:
336 			ieee80211_remain_on_channel_expired(mvm->hw);
337 			iwl_mvm_roc_finished(mvm);
338 			break;
339 		case NL80211_IFTYPE_STATION:
340 			/*
341 			 * By now, we should have finished association
342 			 * and know the dtim period.
343 			 */
344 			iwl_mvm_te_check_disconnect(mvm, te_data->vif,
345 				"No beacon heard and the time event is over already...");
346 			break;
347 		default:
348 			break;
349 		}
350 
351 		iwl_mvm_te_clear_data(mvm, te_data);
352 	} else if (le32_to_cpu(notif->action) & TE_V2_NOTIF_HOST_EVENT_START) {
353 		te_data->running = true;
354 		te_data->end_jiffies = TU_TO_EXP_TIME(te_data->duration);
355 
356 		if (te_data->vif->type == NL80211_IFTYPE_P2P_DEVICE) {
357 			set_bit(IWL_MVM_STATUS_ROC_RUNNING, &mvm->status);
358 			iwl_mvm_ref(mvm, IWL_MVM_REF_ROC);
359 			ieee80211_ready_on_channel(mvm->hw);
360 		} else if (te_data->id == TE_CHANNEL_SWITCH_PERIOD) {
361 			iwl_mvm_te_handle_notify_csa(mvm, te_data, notif);
362 		}
363 	} else {
364 		IWL_WARN(mvm, "Got TE with unknown action\n");
365 	}
366 }
367 
368 /*
369  * Handle A Aux ROC time event
370  */
371 static int iwl_mvm_aux_roc_te_handle_notif(struct iwl_mvm *mvm,
372 					   struct iwl_time_event_notif *notif)
373 {
374 	struct iwl_mvm_time_event_data *te_data, *tmp;
375 	bool aux_roc_te = false;
376 
377 	list_for_each_entry_safe(te_data, tmp, &mvm->aux_roc_te_list, list) {
378 		if (le32_to_cpu(notif->unique_id) == te_data->uid) {
379 			aux_roc_te = true;
380 			break;
381 		}
382 	}
383 	if (!aux_roc_te) /* Not a Aux ROC time event */
384 		return -EINVAL;
385 
386 	iwl_mvm_te_check_trigger(mvm, notif, te_data);
387 
388 	IWL_DEBUG_TE(mvm,
389 		     "Aux ROC time event notification  - UID = 0x%x action %d (error = %d)\n",
390 		     le32_to_cpu(notif->unique_id),
391 		     le32_to_cpu(notif->action), le32_to_cpu(notif->status));
392 
393 	if (!le32_to_cpu(notif->status) ||
394 	    le32_to_cpu(notif->action) == TE_V2_NOTIF_HOST_EVENT_END) {
395 		/* End TE, notify mac80211 */
396 		ieee80211_remain_on_channel_expired(mvm->hw);
397 		iwl_mvm_roc_finished(mvm); /* flush aux queue */
398 		list_del(&te_data->list); /* remove from list */
399 		te_data->running = false;
400 		te_data->vif = NULL;
401 		te_data->uid = 0;
402 		te_data->id = TE_MAX;
403 	} else if (le32_to_cpu(notif->action) == TE_V2_NOTIF_HOST_EVENT_START) {
404 		set_bit(IWL_MVM_STATUS_ROC_AUX_RUNNING, &mvm->status);
405 		te_data->running = true;
406 		iwl_mvm_ref(mvm, IWL_MVM_REF_ROC_AUX);
407 		ieee80211_ready_on_channel(mvm->hw); /* Start TE */
408 	} else {
409 		IWL_DEBUG_TE(mvm,
410 			     "ERROR: Unknown Aux ROC Time Event (action = %d)\n",
411 			     le32_to_cpu(notif->action));
412 		return -EINVAL;
413 	}
414 
415 	return 0;
416 }
417 
418 /*
419  * The Rx handler for time event notifications
420  */
421 void iwl_mvm_rx_time_event_notif(struct iwl_mvm *mvm,
422 				 struct iwl_rx_cmd_buffer *rxb)
423 {
424 	struct iwl_rx_packet *pkt = rxb_addr(rxb);
425 	struct iwl_time_event_notif *notif = (void *)pkt->data;
426 	struct iwl_mvm_time_event_data *te_data, *tmp;
427 
428 	IWL_DEBUG_TE(mvm, "Time event notification - UID = 0x%x action %d\n",
429 		     le32_to_cpu(notif->unique_id),
430 		     le32_to_cpu(notif->action));
431 
432 	spin_lock_bh(&mvm->time_event_lock);
433 	/* This time event is triggered for Aux ROC request */
434 	if (!iwl_mvm_aux_roc_te_handle_notif(mvm, notif))
435 		goto unlock;
436 
437 	list_for_each_entry_safe(te_data, tmp, &mvm->time_event_list, list) {
438 		if (le32_to_cpu(notif->unique_id) == te_data->uid)
439 			iwl_mvm_te_handle_notif(mvm, te_data, notif);
440 	}
441 unlock:
442 	spin_unlock_bh(&mvm->time_event_lock);
443 }
444 
445 static bool iwl_mvm_te_notif(struct iwl_notif_wait_data *notif_wait,
446 			     struct iwl_rx_packet *pkt, void *data)
447 {
448 	struct iwl_mvm *mvm =
449 		container_of(notif_wait, struct iwl_mvm, notif_wait);
450 	struct iwl_mvm_time_event_data *te_data = data;
451 	struct iwl_time_event_notif *resp;
452 	int resp_len = iwl_rx_packet_payload_len(pkt);
453 
454 	if (WARN_ON(pkt->hdr.cmd != TIME_EVENT_NOTIFICATION))
455 		return true;
456 
457 	if (WARN_ON_ONCE(resp_len != sizeof(*resp))) {
458 		IWL_ERR(mvm, "Invalid TIME_EVENT_NOTIFICATION response\n");
459 		return true;
460 	}
461 
462 	resp = (void *)pkt->data;
463 
464 	/* te_data->uid is already set in the TIME_EVENT_CMD response */
465 	if (le32_to_cpu(resp->unique_id) != te_data->uid)
466 		return false;
467 
468 	IWL_DEBUG_TE(mvm, "TIME_EVENT_NOTIFICATION response - UID = 0x%x\n",
469 		     te_data->uid);
470 	if (!resp->status)
471 		IWL_ERR(mvm,
472 			"TIME_EVENT_NOTIFICATION received but not executed\n");
473 
474 	return true;
475 }
476 
477 static bool iwl_mvm_time_event_response(struct iwl_notif_wait_data *notif_wait,
478 					struct iwl_rx_packet *pkt, void *data)
479 {
480 	struct iwl_mvm *mvm =
481 		container_of(notif_wait, struct iwl_mvm, notif_wait);
482 	struct iwl_mvm_time_event_data *te_data = data;
483 	struct iwl_time_event_resp *resp;
484 	int resp_len = iwl_rx_packet_payload_len(pkt);
485 
486 	if (WARN_ON(pkt->hdr.cmd != TIME_EVENT_CMD))
487 		return true;
488 
489 	if (WARN_ON_ONCE(resp_len != sizeof(*resp))) {
490 		IWL_ERR(mvm, "Invalid TIME_EVENT_CMD response\n");
491 		return true;
492 	}
493 
494 	resp = (void *)pkt->data;
495 
496 	/* we should never get a response to another TIME_EVENT_CMD here */
497 	if (WARN_ON_ONCE(le32_to_cpu(resp->id) != te_data->id))
498 		return false;
499 
500 	te_data->uid = le32_to_cpu(resp->unique_id);
501 	IWL_DEBUG_TE(mvm, "TIME_EVENT_CMD response - UID = 0x%x\n",
502 		     te_data->uid);
503 	return true;
504 }
505 
506 static int iwl_mvm_time_event_send_add(struct iwl_mvm *mvm,
507 				       struct ieee80211_vif *vif,
508 				       struct iwl_mvm_time_event_data *te_data,
509 				       struct iwl_time_event_cmd *te_cmd)
510 {
511 	static const u16 time_event_response[] = { TIME_EVENT_CMD };
512 	struct iwl_notification_wait wait_time_event;
513 	int ret;
514 
515 	lockdep_assert_held(&mvm->mutex);
516 
517 	IWL_DEBUG_TE(mvm, "Add new TE, duration %d TU\n",
518 		     le32_to_cpu(te_cmd->duration));
519 
520 	spin_lock_bh(&mvm->time_event_lock);
521 	if (WARN_ON(te_data->id != TE_MAX)) {
522 		spin_unlock_bh(&mvm->time_event_lock);
523 		return -EIO;
524 	}
525 	te_data->vif = vif;
526 	te_data->duration = le32_to_cpu(te_cmd->duration);
527 	te_data->id = le32_to_cpu(te_cmd->id);
528 	list_add_tail(&te_data->list, &mvm->time_event_list);
529 	spin_unlock_bh(&mvm->time_event_lock);
530 
531 	/*
532 	 * Use a notification wait, which really just processes the
533 	 * command response and doesn't wait for anything, in order
534 	 * to be able to process the response and get the UID inside
535 	 * the RX path. Using CMD_WANT_SKB doesn't work because it
536 	 * stores the buffer and then wakes up this thread, by which
537 	 * time another notification (that the time event started)
538 	 * might already be processed unsuccessfully.
539 	 */
540 	iwl_init_notification_wait(&mvm->notif_wait, &wait_time_event,
541 				   time_event_response,
542 				   ARRAY_SIZE(time_event_response),
543 				   iwl_mvm_time_event_response, te_data);
544 
545 	ret = iwl_mvm_send_cmd_pdu(mvm, TIME_EVENT_CMD, 0,
546 					    sizeof(*te_cmd), te_cmd);
547 	if (ret) {
548 		IWL_ERR(mvm, "Couldn't send TIME_EVENT_CMD: %d\n", ret);
549 		iwl_remove_notification(&mvm->notif_wait, &wait_time_event);
550 		goto out_clear_te;
551 	}
552 
553 	/* No need to wait for anything, so just pass 1 (0 isn't valid) */
554 	ret = iwl_wait_notification(&mvm->notif_wait, &wait_time_event, 1);
555 	/* should never fail */
556 	WARN_ON_ONCE(ret);
557 
558 	if (ret) {
559  out_clear_te:
560 		spin_lock_bh(&mvm->time_event_lock);
561 		iwl_mvm_te_clear_data(mvm, te_data);
562 		spin_unlock_bh(&mvm->time_event_lock);
563 	}
564 	return ret;
565 }
566 
567 void iwl_mvm_protect_session(struct iwl_mvm *mvm,
568 			     struct ieee80211_vif *vif,
569 			     u32 duration, u32 min_duration,
570 			     u32 max_delay, bool wait_for_notif)
571 {
572 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
573 	struct iwl_mvm_time_event_data *te_data = &mvmvif->time_event_data;
574 	const u16 te_notif_response[] = { TIME_EVENT_NOTIFICATION };
575 	struct iwl_notification_wait wait_te_notif;
576 	struct iwl_time_event_cmd time_cmd = {};
577 
578 	lockdep_assert_held(&mvm->mutex);
579 
580 	if (te_data->running &&
581 	    time_after(te_data->end_jiffies, TU_TO_EXP_TIME(min_duration))) {
582 		IWL_DEBUG_TE(mvm, "We have enough time in the current TE: %u\n",
583 			     jiffies_to_msecs(te_data->end_jiffies - jiffies));
584 		return;
585 	}
586 
587 	if (te_data->running) {
588 		IWL_DEBUG_TE(mvm, "extend 0x%x: only %u ms left\n",
589 			     te_data->uid,
590 			     jiffies_to_msecs(te_data->end_jiffies - jiffies));
591 		/*
592 		 * we don't have enough time
593 		 * cancel the current TE and issue a new one
594 		 * Of course it would be better to remove the old one only
595 		 * when the new one is added, but we don't care if we are off
596 		 * channel for a bit. All we need to do, is not to return
597 		 * before we actually begin to be on the channel.
598 		 */
599 		iwl_mvm_stop_session_protection(mvm, vif);
600 	}
601 
602 	time_cmd.action = cpu_to_le32(FW_CTXT_ACTION_ADD);
603 	time_cmd.id_and_color =
604 		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
605 	time_cmd.id = cpu_to_le32(TE_BSS_STA_AGGRESSIVE_ASSOC);
606 
607 	time_cmd.apply_time = cpu_to_le32(0);
608 
609 	time_cmd.max_frags = TE_V2_FRAG_NONE;
610 	time_cmd.max_delay = cpu_to_le32(max_delay);
611 	/* TODO: why do we need to interval = bi if it is not periodic? */
612 	time_cmd.interval = cpu_to_le32(1);
613 	time_cmd.duration = cpu_to_le32(duration);
614 	time_cmd.repeat = 1;
615 	time_cmd.policy = cpu_to_le16(TE_V2_NOTIF_HOST_EVENT_START |
616 				      TE_V2_NOTIF_HOST_EVENT_END |
617 				      TE_V2_START_IMMEDIATELY);
618 
619 	if (!wait_for_notif) {
620 		iwl_mvm_time_event_send_add(mvm, vif, te_data, &time_cmd);
621 		return;
622 	}
623 
624 	/*
625 	 * Create notification_wait for the TIME_EVENT_NOTIFICATION to use
626 	 * right after we send the time event
627 	 */
628 	iwl_init_notification_wait(&mvm->notif_wait, &wait_te_notif,
629 				   te_notif_response,
630 				   ARRAY_SIZE(te_notif_response),
631 				   iwl_mvm_te_notif, te_data);
632 
633 	/* If TE was sent OK - wait for the notification that started */
634 	if (iwl_mvm_time_event_send_add(mvm, vif, te_data, &time_cmd)) {
635 		IWL_ERR(mvm, "Failed to add TE to protect session\n");
636 		iwl_remove_notification(&mvm->notif_wait, &wait_te_notif);
637 	} else if (iwl_wait_notification(&mvm->notif_wait, &wait_te_notif,
638 					 TU_TO_JIFFIES(max_delay))) {
639 		IWL_ERR(mvm, "Failed to protect session until TE\n");
640 	}
641 }
642 
643 static bool __iwl_mvm_remove_time_event(struct iwl_mvm *mvm,
644 					struct iwl_mvm_time_event_data *te_data,
645 					u32 *uid)
646 {
647 	u32 id;
648 
649 	/*
650 	 * It is possible that by the time we got to this point the time
651 	 * event was already removed.
652 	 */
653 	spin_lock_bh(&mvm->time_event_lock);
654 
655 	/* Save time event uid before clearing its data */
656 	*uid = te_data->uid;
657 	id = te_data->id;
658 
659 	/*
660 	 * The clear_data function handles time events that were already removed
661 	 */
662 	iwl_mvm_te_clear_data(mvm, te_data);
663 	spin_unlock_bh(&mvm->time_event_lock);
664 
665 	/*
666 	 * It is possible that by the time we try to remove it, the time event
667 	 * has already ended and removed. In such a case there is no need to
668 	 * send a removal command.
669 	 */
670 	if (id == TE_MAX) {
671 		IWL_DEBUG_TE(mvm, "TE 0x%x has already ended\n", *uid);
672 		return false;
673 	}
674 
675 	return true;
676 }
677 
678 /*
679  * Explicit request to remove a aux roc time event. The removal of a time
680  * event needs to be synchronized with the flow of a time event's end
681  * notification, which also removes the time event from the op mode
682  * data structures.
683  */
684 static void iwl_mvm_remove_aux_roc_te(struct iwl_mvm *mvm,
685 				      struct iwl_mvm_vif *mvmvif,
686 				      struct iwl_mvm_time_event_data *te_data)
687 {
688 	struct iwl_hs20_roc_req aux_cmd = {};
689 	u32 uid;
690 	int ret;
691 
692 	if (!__iwl_mvm_remove_time_event(mvm, te_data, &uid))
693 		return;
694 
695 	aux_cmd.event_unique_id = cpu_to_le32(uid);
696 	aux_cmd.action = cpu_to_le32(FW_CTXT_ACTION_REMOVE);
697 	aux_cmd.id_and_color =
698 		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
699 	IWL_DEBUG_TE(mvm, "Removing BSS AUX ROC TE 0x%x\n",
700 		     le32_to_cpu(aux_cmd.event_unique_id));
701 	ret = iwl_mvm_send_cmd_pdu(mvm, HOT_SPOT_CMD, 0,
702 				   sizeof(aux_cmd), &aux_cmd);
703 
704 	if (WARN_ON(ret))
705 		return;
706 }
707 
708 /*
709  * Explicit request to remove a time event. The removal of a time event needs to
710  * be synchronized with the flow of a time event's end notification, which also
711  * removes the time event from the op mode data structures.
712  */
713 void iwl_mvm_remove_time_event(struct iwl_mvm *mvm,
714 			       struct iwl_mvm_vif *mvmvif,
715 			       struct iwl_mvm_time_event_data *te_data)
716 {
717 	struct iwl_time_event_cmd time_cmd = {};
718 	u32 uid;
719 	int ret;
720 
721 	if (!__iwl_mvm_remove_time_event(mvm, te_data, &uid))
722 		return;
723 
724 	/* When we remove a TE, the UID is to be set in the id field */
725 	time_cmd.id = cpu_to_le32(uid);
726 	time_cmd.action = cpu_to_le32(FW_CTXT_ACTION_REMOVE);
727 	time_cmd.id_and_color =
728 		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
729 
730 	IWL_DEBUG_TE(mvm, "Removing TE 0x%x\n", le32_to_cpu(time_cmd.id));
731 	ret = iwl_mvm_send_cmd_pdu(mvm, TIME_EVENT_CMD, 0,
732 				   sizeof(time_cmd), &time_cmd);
733 	if (WARN_ON(ret))
734 		return;
735 }
736 
737 void iwl_mvm_stop_session_protection(struct iwl_mvm *mvm,
738 				     struct ieee80211_vif *vif)
739 {
740 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
741 	struct iwl_mvm_time_event_data *te_data = &mvmvif->time_event_data;
742 	u32 id;
743 
744 	lockdep_assert_held(&mvm->mutex);
745 
746 	spin_lock_bh(&mvm->time_event_lock);
747 	id = te_data->id;
748 	spin_unlock_bh(&mvm->time_event_lock);
749 
750 	if (id != TE_BSS_STA_AGGRESSIVE_ASSOC) {
751 		IWL_DEBUG_TE(mvm,
752 			     "don't remove TE with id=%u (not session protection)\n",
753 			     id);
754 		return;
755 	}
756 
757 	iwl_mvm_remove_time_event(mvm, mvmvif, te_data);
758 }
759 
760 int iwl_mvm_start_p2p_roc(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
761 			  int duration, enum ieee80211_roc_type type)
762 {
763 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
764 	struct iwl_mvm_time_event_data *te_data = &mvmvif->time_event_data;
765 	struct iwl_time_event_cmd time_cmd = {};
766 
767 	lockdep_assert_held(&mvm->mutex);
768 	if (te_data->running) {
769 		IWL_WARN(mvm, "P2P_DEVICE remain on channel already running\n");
770 		return -EBUSY;
771 	}
772 
773 	time_cmd.action = cpu_to_le32(FW_CTXT_ACTION_ADD);
774 	time_cmd.id_and_color =
775 		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
776 
777 	switch (type) {
778 	case IEEE80211_ROC_TYPE_NORMAL:
779 		time_cmd.id = cpu_to_le32(IWL_MVM_ROC_TE_TYPE_NORMAL);
780 		break;
781 	case IEEE80211_ROC_TYPE_MGMT_TX:
782 		time_cmd.id = cpu_to_le32(IWL_MVM_ROC_TE_TYPE_MGMT_TX);
783 		break;
784 	default:
785 		WARN_ONCE(1, "Got an invalid ROC type\n");
786 		return -EINVAL;
787 	}
788 
789 	time_cmd.apply_time = cpu_to_le32(0);
790 	time_cmd.interval = cpu_to_le32(1);
791 
792 	/*
793 	 * The P2P Device TEs can have lower priority than other events
794 	 * that are being scheduled by the driver/fw, and thus it might not be
795 	 * scheduled. To improve the chances of it being scheduled, allow them
796 	 * to be fragmented, and in addition allow them to be delayed.
797 	 */
798 	time_cmd.max_frags = min(MSEC_TO_TU(duration)/50, TE_V2_FRAG_ENDLESS);
799 	time_cmd.max_delay = cpu_to_le32(MSEC_TO_TU(duration/2));
800 	time_cmd.duration = cpu_to_le32(MSEC_TO_TU(duration));
801 	time_cmd.repeat = 1;
802 	time_cmd.policy = cpu_to_le16(TE_V2_NOTIF_HOST_EVENT_START |
803 				      TE_V2_NOTIF_HOST_EVENT_END |
804 				      TE_V2_START_IMMEDIATELY);
805 
806 	return iwl_mvm_time_event_send_add(mvm, vif, te_data, &time_cmd);
807 }
808 
809 static struct iwl_mvm_time_event_data *iwl_mvm_get_roc_te(struct iwl_mvm *mvm)
810 {
811 	struct iwl_mvm_time_event_data *te_data;
812 
813 	lockdep_assert_held(&mvm->mutex);
814 
815 	spin_lock_bh(&mvm->time_event_lock);
816 
817 	/*
818 	 * Iterate over the list of time events and find the time event that is
819 	 * associated with a P2P_DEVICE interface.
820 	 * This assumes that a P2P_DEVICE interface can have only a single time
821 	 * event at any given time and this time event coresponds to a ROC
822 	 * request
823 	 */
824 	list_for_each_entry(te_data, &mvm->time_event_list, list) {
825 		if (te_data->vif->type == NL80211_IFTYPE_P2P_DEVICE)
826 			goto out;
827 	}
828 
829 	/* There can only be at most one AUX ROC time event, we just use the
830 	 * list to simplify/unify code. Remove it if it exists.
831 	 */
832 	te_data = list_first_entry_or_null(&mvm->aux_roc_te_list,
833 					   struct iwl_mvm_time_event_data,
834 					   list);
835 out:
836 	spin_unlock_bh(&mvm->time_event_lock);
837 	return te_data;
838 }
839 
840 void iwl_mvm_cleanup_roc_te(struct iwl_mvm *mvm)
841 {
842 	struct iwl_mvm_time_event_data *te_data;
843 	u32 uid;
844 
845 	te_data = iwl_mvm_get_roc_te(mvm);
846 	if (te_data)
847 		__iwl_mvm_remove_time_event(mvm, te_data, &uid);
848 }
849 
850 void iwl_mvm_stop_roc(struct iwl_mvm *mvm)
851 {
852 	struct iwl_mvm_vif *mvmvif;
853 	struct iwl_mvm_time_event_data *te_data;
854 
855 	te_data = iwl_mvm_get_roc_te(mvm);
856 	if (!te_data) {
857 		IWL_WARN(mvm, "No remain on channel event\n");
858 		return;
859 	}
860 
861 	mvmvif = iwl_mvm_vif_from_mac80211(te_data->vif);
862 
863 	if (te_data->vif->type == NL80211_IFTYPE_P2P_DEVICE) {
864 		iwl_mvm_remove_time_event(mvm, mvmvif, te_data);
865 		set_bit(IWL_MVM_STATUS_NEED_FLUSH_P2P, &mvm->status);
866 	} else {
867 		iwl_mvm_remove_aux_roc_te(mvm, mvmvif, te_data);
868 	}
869 
870 	iwl_mvm_roc_finished(mvm);
871 }
872 
873 int iwl_mvm_schedule_csa_period(struct iwl_mvm *mvm,
874 				struct ieee80211_vif *vif,
875 				u32 duration, u32 apply_time)
876 {
877 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
878 	struct iwl_mvm_time_event_data *te_data = &mvmvif->time_event_data;
879 	struct iwl_time_event_cmd time_cmd = {};
880 
881 	lockdep_assert_held(&mvm->mutex);
882 
883 	if (te_data->running) {
884 		u32 id;
885 
886 		spin_lock_bh(&mvm->time_event_lock);
887 		id = te_data->id;
888 		spin_unlock_bh(&mvm->time_event_lock);
889 
890 		if (id == TE_CHANNEL_SWITCH_PERIOD) {
891 			IWL_DEBUG_TE(mvm, "CS period is already scheduled\n");
892 			return -EBUSY;
893 		}
894 
895 		/*
896 		 * Remove the session protection time event to allow the
897 		 * channel switch. If we got here, we just heard a beacon so
898 		 * the session protection is not needed anymore anyway.
899 		 */
900 		iwl_mvm_remove_time_event(mvm, mvmvif, te_data);
901 	}
902 
903 	time_cmd.action = cpu_to_le32(FW_CTXT_ACTION_ADD);
904 	time_cmd.id_and_color =
905 		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
906 	time_cmd.id = cpu_to_le32(TE_CHANNEL_SWITCH_PERIOD);
907 	time_cmd.apply_time = cpu_to_le32(apply_time);
908 	time_cmd.max_frags = TE_V2_FRAG_NONE;
909 	time_cmd.duration = cpu_to_le32(duration);
910 	time_cmd.repeat = 1;
911 	time_cmd.interval = cpu_to_le32(1);
912 	time_cmd.policy = cpu_to_le16(TE_V2_NOTIF_HOST_EVENT_START |
913 				      TE_V2_ABSENCE);
914 	if (!apply_time)
915 		time_cmd.policy |= cpu_to_le16(TE_V2_START_IMMEDIATELY);
916 
917 	return iwl_mvm_time_event_send_add(mvm, vif, te_data, &time_cmd);
918 }
919