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) 2014 Intel Mobile Communications GmbH
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of version 2 of the GNU General Public License as
12  * published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
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20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
22  * USA
23  *
24  * The full GNU General Public License is included in this distribution
25  * in the file called COPYING.
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28  *  Intel Linux Wireless <linuxwifi@intel.com>
29  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
30  *
31  * BSD LICENSE
32  *
33  * Copyright(c) 2014 Intel Mobile Communications GmbH
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60  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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62  *****************************************************************************/
63 
64 #include <linux/etherdevice.h>
65 #include "mvm.h"
66 #include "time-event.h"
67 #include "iwl-io.h"
68 #include "iwl-prph.h"
69 
70 #define TU_TO_US(x) (x * 1024)
71 #define TU_TO_MS(x) (TU_TO_US(x) / 1000)
72 
73 void iwl_mvm_teardown_tdls_peers(struct iwl_mvm *mvm)
74 {
75 	struct ieee80211_sta *sta;
76 	struct iwl_mvm_sta *mvmsta;
77 	int i;
78 
79 	lockdep_assert_held(&mvm->mutex);
80 
81 	for (i = 0; i < IWL_MVM_STATION_COUNT; i++) {
82 		sta = rcu_dereference_protected(mvm->fw_id_to_mac_id[i],
83 						lockdep_is_held(&mvm->mutex));
84 		if (!sta || IS_ERR(sta) || !sta->tdls)
85 			continue;
86 
87 		mvmsta = iwl_mvm_sta_from_mac80211(sta);
88 		ieee80211_tdls_oper_request(mvmsta->vif, sta->addr,
89 				NL80211_TDLS_TEARDOWN,
90 				WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED,
91 				GFP_KERNEL);
92 	}
93 }
94 
95 int iwl_mvm_tdls_sta_count(struct iwl_mvm *mvm, struct ieee80211_vif *vif)
96 {
97 	struct ieee80211_sta *sta;
98 	struct iwl_mvm_sta *mvmsta;
99 	int count = 0;
100 	int i;
101 
102 	lockdep_assert_held(&mvm->mutex);
103 
104 	for (i = 0; i < IWL_MVM_STATION_COUNT; i++) {
105 		sta = rcu_dereference_protected(mvm->fw_id_to_mac_id[i],
106 						lockdep_is_held(&mvm->mutex));
107 		if (!sta || IS_ERR(sta) || !sta->tdls)
108 			continue;
109 
110 		if (vif) {
111 			mvmsta = iwl_mvm_sta_from_mac80211(sta);
112 			if (mvmsta->vif != vif)
113 				continue;
114 		}
115 
116 		count++;
117 	}
118 
119 	return count;
120 }
121 
122 static void iwl_mvm_tdls_config(struct iwl_mvm *mvm, struct ieee80211_vif *vif)
123 {
124 	struct iwl_rx_packet *pkt;
125 	struct iwl_tdls_config_res *resp;
126 	struct iwl_tdls_config_cmd tdls_cfg_cmd = {};
127 	struct iwl_host_cmd cmd = {
128 		.id = TDLS_CONFIG_CMD,
129 		.flags = CMD_WANT_SKB,
130 		.data = { &tdls_cfg_cmd, },
131 		.len = { sizeof(struct iwl_tdls_config_cmd), },
132 	};
133 	struct ieee80211_sta *sta;
134 	int ret, i, cnt;
135 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
136 
137 	lockdep_assert_held(&mvm->mutex);
138 
139 	tdls_cfg_cmd.id_and_color =
140 		cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color));
141 	tdls_cfg_cmd.tx_to_ap_tid = IWL_MVM_TDLS_FW_TID;
142 	tdls_cfg_cmd.tx_to_ap_ssn = cpu_to_le16(0); /* not used for now */
143 
144 	/* for now the Tx cmd is empty and unused */
145 
146 	/* populate TDLS peer data */
147 	cnt = 0;
148 	for (i = 0; i < IWL_MVM_STATION_COUNT; i++) {
149 		sta = rcu_dereference_protected(mvm->fw_id_to_mac_id[i],
150 						lockdep_is_held(&mvm->mutex));
151 		if (IS_ERR_OR_NULL(sta) || !sta->tdls)
152 			continue;
153 
154 		tdls_cfg_cmd.sta_info[cnt].sta_id = i;
155 		tdls_cfg_cmd.sta_info[cnt].tx_to_peer_tid =
156 							IWL_MVM_TDLS_FW_TID;
157 		tdls_cfg_cmd.sta_info[cnt].tx_to_peer_ssn = cpu_to_le16(0);
158 		tdls_cfg_cmd.sta_info[cnt].is_initiator =
159 				cpu_to_le32(sta->tdls_initiator ? 1 : 0);
160 
161 		cnt++;
162 	}
163 
164 	tdls_cfg_cmd.tdls_peer_count = cnt;
165 	IWL_DEBUG_TDLS(mvm, "send TDLS config to FW for %d peers\n", cnt);
166 
167 	ret = iwl_mvm_send_cmd(mvm, &cmd);
168 	if (WARN_ON_ONCE(ret))
169 		return;
170 
171 	pkt = cmd.resp_pkt;
172 
173 	WARN_ON_ONCE(iwl_rx_packet_payload_len(pkt) != sizeof(*resp));
174 
175 	/* we don't really care about the response at this point */
176 
177 	iwl_free_resp(&cmd);
178 }
179 
180 void iwl_mvm_recalc_tdls_state(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
181 			       bool sta_added)
182 {
183 	int tdls_sta_cnt = iwl_mvm_tdls_sta_count(mvm, vif);
184 
185 	/* when the first peer joins, send a power update first */
186 	if (tdls_sta_cnt == 1 && sta_added)
187 		iwl_mvm_power_update_mac(mvm);
188 
189 	/* configure the FW with TDLS peer info */
190 	iwl_mvm_tdls_config(mvm, vif);
191 
192 	/* when the last peer leaves, send a power update last */
193 	if (tdls_sta_cnt == 0 && !sta_added)
194 		iwl_mvm_power_update_mac(mvm);
195 }
196 
197 void iwl_mvm_mac_mgd_protect_tdls_discover(struct ieee80211_hw *hw,
198 					   struct ieee80211_vif *vif)
199 {
200 	struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
201 	u32 duration = 2 * vif->bss_conf.dtim_period * vif->bss_conf.beacon_int;
202 
203 	/*
204 	 * iwl_mvm_protect_session() reads directly from the device
205 	 * (the system time), so make sure it is available.
206 	 */
207 	if (iwl_mvm_ref_sync(mvm, IWL_MVM_REF_PROTECT_TDLS))
208 		return;
209 
210 	mutex_lock(&mvm->mutex);
211 	/* Protect the session to hear the TDLS setup response on the channel */
212 	iwl_mvm_protect_session(mvm, vif, duration, duration, 100, true);
213 	mutex_unlock(&mvm->mutex);
214 
215 	iwl_mvm_unref(mvm, IWL_MVM_REF_PROTECT_TDLS);
216 }
217 
218 static const char *
219 iwl_mvm_tdls_cs_state_str(enum iwl_mvm_tdls_cs_state state)
220 {
221 	switch (state) {
222 	case IWL_MVM_TDLS_SW_IDLE:
223 		return "IDLE";
224 	case IWL_MVM_TDLS_SW_REQ_SENT:
225 		return "REQ SENT";
226 	case IWL_MVM_TDLS_SW_RESP_RCVD:
227 		return "RESP RECEIVED";
228 	case IWL_MVM_TDLS_SW_REQ_RCVD:
229 		return "REQ RECEIVED";
230 	case IWL_MVM_TDLS_SW_ACTIVE:
231 		return "ACTIVE";
232 	}
233 
234 	return NULL;
235 }
236 
237 static void iwl_mvm_tdls_update_cs_state(struct iwl_mvm *mvm,
238 					 enum iwl_mvm_tdls_cs_state state)
239 {
240 	if (mvm->tdls_cs.state == state)
241 		return;
242 
243 	IWL_DEBUG_TDLS(mvm, "TDLS channel switch state: %s -> %s\n",
244 		       iwl_mvm_tdls_cs_state_str(mvm->tdls_cs.state),
245 		       iwl_mvm_tdls_cs_state_str(state));
246 	mvm->tdls_cs.state = state;
247 
248 	/* we only send requests to our switching peer - update sent time */
249 	if (state == IWL_MVM_TDLS_SW_REQ_SENT)
250 		mvm->tdls_cs.peer.sent_timestamp =
251 			iwl_read_prph(mvm->trans, DEVICE_SYSTEM_TIME_REG);
252 
253 	if (state == IWL_MVM_TDLS_SW_IDLE)
254 		mvm->tdls_cs.cur_sta_id = IWL_MVM_STATION_COUNT;
255 }
256 
257 void iwl_mvm_rx_tdls_notif(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb)
258 {
259 	struct iwl_rx_packet *pkt = rxb_addr(rxb);
260 	struct iwl_tdls_channel_switch_notif *notif = (void *)pkt->data;
261 	struct ieee80211_sta *sta;
262 	unsigned int delay;
263 	struct iwl_mvm_sta *mvmsta;
264 	struct ieee80211_vif *vif;
265 	u32 sta_id = le32_to_cpu(notif->sta_id);
266 
267 	lockdep_assert_held(&mvm->mutex);
268 
269 	/* can fail sometimes */
270 	if (!le32_to_cpu(notif->status)) {
271 		iwl_mvm_tdls_update_cs_state(mvm, IWL_MVM_TDLS_SW_IDLE);
272 		return;
273 	}
274 
275 	if (WARN_ON(sta_id >= IWL_MVM_STATION_COUNT))
276 		return;
277 
278 	sta = rcu_dereference_protected(mvm->fw_id_to_mac_id[sta_id],
279 					lockdep_is_held(&mvm->mutex));
280 	/* the station may not be here, but if it is, it must be a TDLS peer */
281 	if (IS_ERR_OR_NULL(sta) || WARN_ON(!sta->tdls))
282 		return;
283 
284 	mvmsta = iwl_mvm_sta_from_mac80211(sta);
285 	vif = mvmsta->vif;
286 
287 	/*
288 	 * Update state and possibly switch again after this is over (DTIM).
289 	 * Also convert TU to msec.
290 	 */
291 	delay = TU_TO_MS(vif->bss_conf.dtim_period * vif->bss_conf.beacon_int);
292 	mod_delayed_work(system_wq, &mvm->tdls_cs.dwork,
293 			 msecs_to_jiffies(delay));
294 
295 	iwl_mvm_tdls_update_cs_state(mvm, IWL_MVM_TDLS_SW_ACTIVE);
296 }
297 
298 static int
299 iwl_mvm_tdls_check_action(struct iwl_mvm *mvm,
300 			  enum iwl_tdls_channel_switch_type type,
301 			  const u8 *peer, bool peer_initiator, u32 timestamp)
302 {
303 	bool same_peer = false;
304 	int ret = 0;
305 
306 	/* get the existing peer if it's there */
307 	if (mvm->tdls_cs.state != IWL_MVM_TDLS_SW_IDLE &&
308 	    mvm->tdls_cs.cur_sta_id != IWL_MVM_STATION_COUNT) {
309 		struct ieee80211_sta *sta = rcu_dereference_protected(
310 				mvm->fw_id_to_mac_id[mvm->tdls_cs.cur_sta_id],
311 				lockdep_is_held(&mvm->mutex));
312 		if (!IS_ERR_OR_NULL(sta))
313 			same_peer = ether_addr_equal(peer, sta->addr);
314 	}
315 
316 	switch (mvm->tdls_cs.state) {
317 	case IWL_MVM_TDLS_SW_IDLE:
318 		/*
319 		 * might be spurious packet from the peer after the switch is
320 		 * already done
321 		 */
322 		if (type == TDLS_MOVE_CH)
323 			ret = -EINVAL;
324 		break;
325 	case IWL_MVM_TDLS_SW_REQ_SENT:
326 		/* only allow requests from the same peer */
327 		if (!same_peer)
328 			ret = -EBUSY;
329 		else if (type == TDLS_SEND_CHAN_SW_RESP_AND_MOVE_CH &&
330 			 !peer_initiator)
331 			/*
332 			 * We received a ch-switch request while an outgoing
333 			 * one is pending. Allow it if the peer is the link
334 			 * initiator.
335 			 */
336 			ret = -EBUSY;
337 		else if (type == TDLS_SEND_CHAN_SW_REQ)
338 			/* wait for idle before sending another request */
339 			ret = -EBUSY;
340 		else if (timestamp <= mvm->tdls_cs.peer.sent_timestamp)
341 			/* we got a stale response - ignore it */
342 			ret = -EINVAL;
343 		break;
344 	case IWL_MVM_TDLS_SW_RESP_RCVD:
345 		/*
346 		 * we are waiting for the FW to give an "active" notification,
347 		 * so ignore requests in the meantime
348 		 */
349 		ret = -EBUSY;
350 		break;
351 	case IWL_MVM_TDLS_SW_REQ_RCVD:
352 		/* as above, allow the link initiator to proceed */
353 		if (type == TDLS_SEND_CHAN_SW_REQ) {
354 			if (!same_peer)
355 				ret = -EBUSY;
356 			else if (peer_initiator) /* they are the initiator */
357 				ret = -EBUSY;
358 		} else if (type == TDLS_MOVE_CH) {
359 			ret = -EINVAL;
360 		}
361 		break;
362 	case IWL_MVM_TDLS_SW_ACTIVE:
363 		/*
364 		 * the only valid request when active is a request to return
365 		 * to the base channel by the current off-channel peer
366 		 */
367 		if (type != TDLS_MOVE_CH || !same_peer)
368 			ret = -EBUSY;
369 		break;
370 	}
371 
372 	if (ret)
373 		IWL_DEBUG_TDLS(mvm,
374 			       "Invalid TDLS action %d state %d peer %pM same_peer %d initiator %d\n",
375 			       type, mvm->tdls_cs.state, peer, same_peer,
376 			       peer_initiator);
377 
378 	return ret;
379 }
380 
381 static int
382 iwl_mvm_tdls_config_channel_switch(struct iwl_mvm *mvm,
383 				   struct ieee80211_vif *vif,
384 				   enum iwl_tdls_channel_switch_type type,
385 				   const u8 *peer, bool peer_initiator,
386 				   u8 oper_class,
387 				   struct cfg80211_chan_def *chandef,
388 				   u32 timestamp, u16 switch_time,
389 				   u16 switch_timeout, struct sk_buff *skb,
390 				   u32 ch_sw_tm_ie)
391 {
392 	struct ieee80211_sta *sta;
393 	struct iwl_mvm_sta *mvmsta;
394 	struct ieee80211_tx_info *info;
395 	struct ieee80211_hdr *hdr;
396 	struct iwl_tdls_channel_switch_cmd cmd = {0};
397 	int ret;
398 
399 	lockdep_assert_held(&mvm->mutex);
400 
401 	ret = iwl_mvm_tdls_check_action(mvm, type, peer, peer_initiator,
402 					timestamp);
403 	if (ret)
404 		return ret;
405 
406 	if (!skb || WARN_ON(skb->len > IWL_TDLS_CH_SW_FRAME_MAX_SIZE)) {
407 		ret = -EINVAL;
408 		goto out;
409 	}
410 
411 	cmd.switch_type = type;
412 	cmd.timing.frame_timestamp = cpu_to_le32(timestamp);
413 	cmd.timing.switch_time = cpu_to_le32(switch_time);
414 	cmd.timing.switch_timeout = cpu_to_le32(switch_timeout);
415 
416 	rcu_read_lock();
417 	sta = ieee80211_find_sta(vif, peer);
418 	if (!sta) {
419 		rcu_read_unlock();
420 		ret = -ENOENT;
421 		goto out;
422 	}
423 	mvmsta = iwl_mvm_sta_from_mac80211(sta);
424 	cmd.peer_sta_id = cpu_to_le32(mvmsta->sta_id);
425 
426 	if (!chandef) {
427 		if (mvm->tdls_cs.state == IWL_MVM_TDLS_SW_REQ_SENT &&
428 		    mvm->tdls_cs.peer.chandef.chan) {
429 			/* actually moving to the channel */
430 			chandef = &mvm->tdls_cs.peer.chandef;
431 		} else if (mvm->tdls_cs.state == IWL_MVM_TDLS_SW_ACTIVE &&
432 			   type == TDLS_MOVE_CH) {
433 			/* we need to return to base channel */
434 			struct ieee80211_chanctx_conf *chanctx =
435 					rcu_dereference(vif->chanctx_conf);
436 
437 			if (WARN_ON_ONCE(!chanctx)) {
438 				rcu_read_unlock();
439 				goto out;
440 			}
441 
442 			chandef = &chanctx->def;
443 		}
444 	}
445 
446 	if (chandef) {
447 		cmd.ci.band = (chandef->chan->band == NL80211_BAND_2GHZ ?
448 			       PHY_BAND_24 : PHY_BAND_5);
449 		cmd.ci.channel = chandef->chan->hw_value;
450 		cmd.ci.width = iwl_mvm_get_channel_width(chandef);
451 		cmd.ci.ctrl_pos = iwl_mvm_get_ctrl_pos(chandef);
452 	}
453 
454 	/* keep quota calculation simple for now - 50% of DTIM for TDLS */
455 	cmd.timing.max_offchan_duration =
456 			cpu_to_le32(TU_TO_US(vif->bss_conf.dtim_period *
457 					     vif->bss_conf.beacon_int) / 2);
458 
459 	/* Switch time is the first element in the switch-timing IE. */
460 	cmd.frame.switch_time_offset = cpu_to_le32(ch_sw_tm_ie + 2);
461 
462 	info = IEEE80211_SKB_CB(skb);
463 	hdr = (void *)skb->data;
464 	if (info->control.hw_key) {
465 		if (info->control.hw_key->cipher != WLAN_CIPHER_SUITE_CCMP) {
466 			rcu_read_unlock();
467 			ret = -EINVAL;
468 			goto out;
469 		}
470 		iwl_mvm_set_tx_cmd_ccmp(info, &cmd.frame.tx_cmd);
471 	}
472 
473 	iwl_mvm_set_tx_cmd(mvm, skb, &cmd.frame.tx_cmd, info,
474 			   mvmsta->sta_id);
475 
476 	iwl_mvm_set_tx_cmd_rate(mvm, &cmd.frame.tx_cmd, info, sta,
477 				hdr->frame_control);
478 	rcu_read_unlock();
479 
480 	memcpy(cmd.frame.data, skb->data, skb->len);
481 
482 	ret = iwl_mvm_send_cmd_pdu(mvm, TDLS_CHANNEL_SWITCH_CMD, 0,
483 				   sizeof(cmd), &cmd);
484 	if (ret) {
485 		IWL_ERR(mvm, "Failed to send TDLS_CHANNEL_SWITCH cmd: %d\n",
486 			ret);
487 		goto out;
488 	}
489 
490 	/* channel switch has started, update state */
491 	if (type != TDLS_MOVE_CH) {
492 		mvm->tdls_cs.cur_sta_id = mvmsta->sta_id;
493 		iwl_mvm_tdls_update_cs_state(mvm,
494 					     type == TDLS_SEND_CHAN_SW_REQ ?
495 					     IWL_MVM_TDLS_SW_REQ_SENT :
496 					     IWL_MVM_TDLS_SW_REQ_RCVD);
497 	} else {
498 		iwl_mvm_tdls_update_cs_state(mvm, IWL_MVM_TDLS_SW_RESP_RCVD);
499 	}
500 
501 out:
502 
503 	/* channel switch failed - we are idle */
504 	if (ret)
505 		iwl_mvm_tdls_update_cs_state(mvm, IWL_MVM_TDLS_SW_IDLE);
506 
507 	return ret;
508 }
509 
510 void iwl_mvm_tdls_ch_switch_work(struct work_struct *work)
511 {
512 	struct iwl_mvm *mvm;
513 	struct ieee80211_sta *sta;
514 	struct iwl_mvm_sta *mvmsta;
515 	struct ieee80211_vif *vif;
516 	unsigned int delay;
517 	int ret;
518 
519 	mvm = container_of(work, struct iwl_mvm, tdls_cs.dwork.work);
520 	mutex_lock(&mvm->mutex);
521 
522 	/* called after an active channel switch has finished or timed-out */
523 	iwl_mvm_tdls_update_cs_state(mvm, IWL_MVM_TDLS_SW_IDLE);
524 
525 	/* station might be gone, in that case do nothing */
526 	if (mvm->tdls_cs.peer.sta_id == IWL_MVM_STATION_COUNT)
527 		goto out;
528 
529 	sta = rcu_dereference_protected(
530 				mvm->fw_id_to_mac_id[mvm->tdls_cs.peer.sta_id],
531 				lockdep_is_held(&mvm->mutex));
532 	/* the station may not be here, but if it is, it must be a TDLS peer */
533 	if (!sta || IS_ERR(sta) || WARN_ON(!sta->tdls))
534 		goto out;
535 
536 	mvmsta = iwl_mvm_sta_from_mac80211(sta);
537 	vif = mvmsta->vif;
538 	ret = iwl_mvm_tdls_config_channel_switch(mvm, vif,
539 						 TDLS_SEND_CHAN_SW_REQ,
540 						 sta->addr,
541 						 mvm->tdls_cs.peer.initiator,
542 						 mvm->tdls_cs.peer.op_class,
543 						 &mvm->tdls_cs.peer.chandef,
544 						 0, 0, 0,
545 						 mvm->tdls_cs.peer.skb,
546 						 mvm->tdls_cs.peer.ch_sw_tm_ie);
547 	if (ret)
548 		IWL_ERR(mvm, "Not sending TDLS channel switch: %d\n", ret);
549 
550 	/* retry after a DTIM if we failed sending now */
551 	delay = TU_TO_MS(vif->bss_conf.dtim_period * vif->bss_conf.beacon_int);
552 	queue_delayed_work(system_wq, &mvm->tdls_cs.dwork,
553 			   msecs_to_jiffies(delay));
554 out:
555 	mutex_unlock(&mvm->mutex);
556 }
557 
558 int
559 iwl_mvm_tdls_channel_switch(struct ieee80211_hw *hw,
560 			    struct ieee80211_vif *vif,
561 			    struct ieee80211_sta *sta, u8 oper_class,
562 			    struct cfg80211_chan_def *chandef,
563 			    struct sk_buff *tmpl_skb, u32 ch_sw_tm_ie)
564 {
565 	struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
566 	struct iwl_mvm_sta *mvmsta;
567 	unsigned int delay;
568 	int ret;
569 
570 	mutex_lock(&mvm->mutex);
571 
572 	IWL_DEBUG_TDLS(mvm, "TDLS channel switch with %pM ch %d width %d\n",
573 		       sta->addr, chandef->chan->center_freq, chandef->width);
574 
575 	/* we only support a single peer for channel switching */
576 	if (mvm->tdls_cs.peer.sta_id != IWL_MVM_STATION_COUNT) {
577 		IWL_DEBUG_TDLS(mvm,
578 			       "Existing peer. Can't start switch with %pM\n",
579 			       sta->addr);
580 		ret = -EBUSY;
581 		goto out;
582 	}
583 
584 	ret = iwl_mvm_tdls_config_channel_switch(mvm, vif,
585 						 TDLS_SEND_CHAN_SW_REQ,
586 						 sta->addr, sta->tdls_initiator,
587 						 oper_class, chandef, 0, 0, 0,
588 						 tmpl_skb, ch_sw_tm_ie);
589 	if (ret)
590 		goto out;
591 
592 	/*
593 	 * Mark the peer as "in tdls switch" for this vif. We only allow a
594 	 * single such peer per vif.
595 	 */
596 	mvm->tdls_cs.peer.skb = skb_copy(tmpl_skb, GFP_KERNEL);
597 	if (!mvm->tdls_cs.peer.skb) {
598 		ret = -ENOMEM;
599 		goto out;
600 	}
601 
602 	mvmsta = iwl_mvm_sta_from_mac80211(sta);
603 	mvm->tdls_cs.peer.sta_id = mvmsta->sta_id;
604 	mvm->tdls_cs.peer.chandef = *chandef;
605 	mvm->tdls_cs.peer.initiator = sta->tdls_initiator;
606 	mvm->tdls_cs.peer.op_class = oper_class;
607 	mvm->tdls_cs.peer.ch_sw_tm_ie = ch_sw_tm_ie;
608 
609 	/*
610 	 * Wait for 2 DTIM periods before attempting the next switch. The next
611 	 * switch will be made sooner if the current one completes before that.
612 	 */
613 	delay = 2 * TU_TO_MS(vif->bss_conf.dtim_period *
614 			     vif->bss_conf.beacon_int);
615 	mod_delayed_work(system_wq, &mvm->tdls_cs.dwork,
616 			 msecs_to_jiffies(delay));
617 
618 out:
619 	mutex_unlock(&mvm->mutex);
620 	return ret;
621 }
622 
623 void iwl_mvm_tdls_cancel_channel_switch(struct ieee80211_hw *hw,
624 					struct ieee80211_vif *vif,
625 					struct ieee80211_sta *sta)
626 {
627 	struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
628 	struct ieee80211_sta *cur_sta;
629 	bool wait_for_phy = false;
630 
631 	mutex_lock(&mvm->mutex);
632 
633 	IWL_DEBUG_TDLS(mvm, "TDLS cancel channel switch with %pM\n", sta->addr);
634 
635 	/* we only support a single peer for channel switching */
636 	if (mvm->tdls_cs.peer.sta_id == IWL_MVM_STATION_COUNT) {
637 		IWL_DEBUG_TDLS(mvm, "No ch switch peer - %pM\n", sta->addr);
638 		goto out;
639 	}
640 
641 	cur_sta = rcu_dereference_protected(
642 				mvm->fw_id_to_mac_id[mvm->tdls_cs.peer.sta_id],
643 				lockdep_is_held(&mvm->mutex));
644 	/* make sure it's the same peer */
645 	if (cur_sta != sta)
646 		goto out;
647 
648 	/*
649 	 * If we're currently in a switch because of the now canceled peer,
650 	 * wait a DTIM here to make sure the phy is back on the base channel.
651 	 * We can't otherwise force it.
652 	 */
653 	if (mvm->tdls_cs.cur_sta_id == mvm->tdls_cs.peer.sta_id &&
654 	    mvm->tdls_cs.state != IWL_MVM_TDLS_SW_IDLE)
655 		wait_for_phy = true;
656 
657 	mvm->tdls_cs.peer.sta_id = IWL_MVM_STATION_COUNT;
658 	dev_kfree_skb(mvm->tdls_cs.peer.skb);
659 	mvm->tdls_cs.peer.skb = NULL;
660 
661 out:
662 	mutex_unlock(&mvm->mutex);
663 
664 	/* make sure the phy is on the base channel */
665 	if (wait_for_phy)
666 		msleep(TU_TO_MS(vif->bss_conf.dtim_period *
667 				vif->bss_conf.beacon_int));
668 
669 	/* flush the channel switch state */
670 	flush_delayed_work(&mvm->tdls_cs.dwork);
671 
672 	IWL_DEBUG_TDLS(mvm, "TDLS ending channel switch with %pM\n", sta->addr);
673 }
674 
675 void
676 iwl_mvm_tdls_recv_channel_switch(struct ieee80211_hw *hw,
677 				 struct ieee80211_vif *vif,
678 				 struct ieee80211_tdls_ch_sw_params *params)
679 {
680 	struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
681 	enum iwl_tdls_channel_switch_type type;
682 	unsigned int delay;
683 	const char *action_str =
684 		params->action_code == WLAN_TDLS_CHANNEL_SWITCH_REQUEST ?
685 		"REQ" : "RESP";
686 
687 	mutex_lock(&mvm->mutex);
688 
689 	IWL_DEBUG_TDLS(mvm,
690 		       "Received TDLS ch switch action %s from %pM status %d\n",
691 		       action_str, params->sta->addr, params->status);
692 
693 	/*
694 	 * we got a non-zero status from a peer we were switching to - move to
695 	 * the idle state and retry again later
696 	 */
697 	if (params->action_code == WLAN_TDLS_CHANNEL_SWITCH_RESPONSE &&
698 	    params->status != 0 &&
699 	    mvm->tdls_cs.state == IWL_MVM_TDLS_SW_REQ_SENT &&
700 	    mvm->tdls_cs.cur_sta_id != IWL_MVM_STATION_COUNT) {
701 		struct ieee80211_sta *cur_sta;
702 
703 		/* make sure it's the same peer */
704 		cur_sta = rcu_dereference_protected(
705 				mvm->fw_id_to_mac_id[mvm->tdls_cs.cur_sta_id],
706 				lockdep_is_held(&mvm->mutex));
707 		if (cur_sta == params->sta) {
708 			iwl_mvm_tdls_update_cs_state(mvm,
709 						     IWL_MVM_TDLS_SW_IDLE);
710 			goto retry;
711 		}
712 	}
713 
714 	type = (params->action_code == WLAN_TDLS_CHANNEL_SWITCH_REQUEST) ?
715 	       TDLS_SEND_CHAN_SW_RESP_AND_MOVE_CH : TDLS_MOVE_CH;
716 
717 	iwl_mvm_tdls_config_channel_switch(mvm, vif, type, params->sta->addr,
718 					   params->sta->tdls_initiator, 0,
719 					   params->chandef, params->timestamp,
720 					   params->switch_time,
721 					   params->switch_timeout,
722 					   params->tmpl_skb,
723 					   params->ch_sw_tm_ie);
724 
725 retry:
726 	/* register a timeout in case we don't succeed in switching */
727 	delay = vif->bss_conf.dtim_period * vif->bss_conf.beacon_int *
728 		1024 / 1000;
729 	mod_delayed_work(system_wq, &mvm->tdls_cs.dwork,
730 			 msecs_to_jiffies(delay));
731 	mutex_unlock(&mvm->mutex);
732 }
733