xref: /linux/net/mac80211/ht.c (revision 63307d015b91e626c97bb82e88054af3d0b74643)
1 /*
2  * HT handling
3  *
4  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
5  * Copyright 2002-2005, Instant802 Networks, Inc.
6  * Copyright 2005-2006, Devicescape Software, Inc.
7  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9  * Copyright 2007-2010, Intel Corporation
10  * Copyright 2017	Intel Deutschland GmbH
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15  */
16 
17 #include <linux/ieee80211.h>
18 #include <linux/export.h>
19 #include <net/mac80211.h>
20 #include "ieee80211_i.h"
21 #include "rate.h"
22 
23 static void __check_htcap_disable(struct ieee80211_ht_cap *ht_capa,
24 				  struct ieee80211_ht_cap *ht_capa_mask,
25 				  struct ieee80211_sta_ht_cap *ht_cap,
26 				  u16 flag)
27 {
28 	__le16 le_flag = cpu_to_le16(flag);
29 	if (ht_capa_mask->cap_info & le_flag) {
30 		if (!(ht_capa->cap_info & le_flag))
31 			ht_cap->cap &= ~flag;
32 	}
33 }
34 
35 static void __check_htcap_enable(struct ieee80211_ht_cap *ht_capa,
36 				  struct ieee80211_ht_cap *ht_capa_mask,
37 				  struct ieee80211_sta_ht_cap *ht_cap,
38 				  u16 flag)
39 {
40 	__le16 le_flag = cpu_to_le16(flag);
41 
42 	if ((ht_capa_mask->cap_info & le_flag) &&
43 	    (ht_capa->cap_info & le_flag))
44 		ht_cap->cap |= flag;
45 }
46 
47 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
48 				     struct ieee80211_sta_ht_cap *ht_cap)
49 {
50 	struct ieee80211_ht_cap *ht_capa, *ht_capa_mask;
51 	u8 *scaps, *smask;
52 	int i;
53 
54 	if (!ht_cap->ht_supported)
55 		return;
56 
57 	switch (sdata->vif.type) {
58 	case NL80211_IFTYPE_STATION:
59 		ht_capa = &sdata->u.mgd.ht_capa;
60 		ht_capa_mask = &sdata->u.mgd.ht_capa_mask;
61 		break;
62 	case NL80211_IFTYPE_ADHOC:
63 		ht_capa = &sdata->u.ibss.ht_capa;
64 		ht_capa_mask = &sdata->u.ibss.ht_capa_mask;
65 		break;
66 	default:
67 		WARN_ON_ONCE(1);
68 		return;
69 	}
70 
71 	scaps = (u8 *)(&ht_capa->mcs.rx_mask);
72 	smask = (u8 *)(&ht_capa_mask->mcs.rx_mask);
73 
74 	/* NOTE:  If you add more over-rides here, update register_hw
75 	 * ht_capa_mod_mask logic in main.c as well.
76 	 * And, if this method can ever change ht_cap.ht_supported, fix
77 	 * the check in ieee80211_add_ht_ie.
78 	 */
79 
80 	/* check for HT over-rides, MCS rates first. */
81 	for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
82 		u8 m = smask[i];
83 		ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
84 		/* Add back rates that are supported */
85 		ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
86 	}
87 
88 	/* Force removal of HT-40 capabilities? */
89 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
90 			      IEEE80211_HT_CAP_SUP_WIDTH_20_40);
91 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
92 			      IEEE80211_HT_CAP_SGI_40);
93 
94 	/* Allow user to disable SGI-20 (SGI-40 is handled above) */
95 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
96 			      IEEE80211_HT_CAP_SGI_20);
97 
98 	/* Allow user to disable the max-AMSDU bit. */
99 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
100 			      IEEE80211_HT_CAP_MAX_AMSDU);
101 
102 	/* Allow user to disable LDPC */
103 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
104 			      IEEE80211_HT_CAP_LDPC_CODING);
105 
106 	/* Allow user to enable 40 MHz intolerant bit. */
107 	__check_htcap_enable(ht_capa, ht_capa_mask, ht_cap,
108 			     IEEE80211_HT_CAP_40MHZ_INTOLERANT);
109 
110 	/* Allow user to enable TX STBC bit  */
111 	__check_htcap_enable(ht_capa, ht_capa_mask, ht_cap,
112 			     IEEE80211_HT_CAP_TX_STBC);
113 
114 	/* Allow user to configure RX STBC bits */
115 	if (ht_capa_mask->cap_info & cpu_to_le16(IEEE80211_HT_CAP_RX_STBC))
116 		ht_cap->cap |= le16_to_cpu(ht_capa->cap_info) &
117 					IEEE80211_HT_CAP_RX_STBC;
118 
119 	/* Allow user to decrease AMPDU factor */
120 	if (ht_capa_mask->ampdu_params_info &
121 	    IEEE80211_HT_AMPDU_PARM_FACTOR) {
122 		u8 n = ht_capa->ampdu_params_info &
123 		       IEEE80211_HT_AMPDU_PARM_FACTOR;
124 		if (n < ht_cap->ampdu_factor)
125 			ht_cap->ampdu_factor = n;
126 	}
127 
128 	/* Allow the user to increase AMPDU density. */
129 	if (ht_capa_mask->ampdu_params_info &
130 	    IEEE80211_HT_AMPDU_PARM_DENSITY) {
131 		u8 n = (ht_capa->ampdu_params_info &
132 			IEEE80211_HT_AMPDU_PARM_DENSITY)
133 			>> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
134 		if (n > ht_cap->ampdu_density)
135 			ht_cap->ampdu_density = n;
136 	}
137 }
138 
139 
140 bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
141 				       struct ieee80211_supported_band *sband,
142 				       const struct ieee80211_ht_cap *ht_cap_ie,
143 				       struct sta_info *sta)
144 {
145 	struct ieee80211_sta_ht_cap ht_cap, own_cap;
146 	u8 ampdu_info, tx_mcs_set_cap;
147 	int i, max_tx_streams;
148 	bool changed;
149 	enum ieee80211_sta_rx_bandwidth bw;
150 	enum ieee80211_smps_mode smps_mode;
151 
152 	memset(&ht_cap, 0, sizeof(ht_cap));
153 
154 	if (!ht_cap_ie || !sband->ht_cap.ht_supported)
155 		goto apply;
156 
157 	ht_cap.ht_supported = true;
158 
159 	own_cap = sband->ht_cap;
160 
161 	/*
162 	 * If user has specified capability over-rides, take care
163 	 * of that if the station we're setting up is the AP or TDLS peer that
164 	 * we advertised a restricted capability set to. Override
165 	 * our own capabilities and then use those below.
166 	 */
167 	if (sdata->vif.type == NL80211_IFTYPE_STATION ||
168 	    sdata->vif.type == NL80211_IFTYPE_ADHOC)
169 		ieee80211_apply_htcap_overrides(sdata, &own_cap);
170 
171 	/*
172 	 * The bits listed in this expression should be
173 	 * the same for the peer and us, if the station
174 	 * advertises more then we can't use those thus
175 	 * we mask them out.
176 	 */
177 	ht_cap.cap = le16_to_cpu(ht_cap_ie->cap_info) &
178 		(own_cap.cap | ~(IEEE80211_HT_CAP_LDPC_CODING |
179 				 IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
180 				 IEEE80211_HT_CAP_GRN_FLD |
181 				 IEEE80211_HT_CAP_SGI_20 |
182 				 IEEE80211_HT_CAP_SGI_40 |
183 				 IEEE80211_HT_CAP_DSSSCCK40));
184 
185 	/*
186 	 * The STBC bits are asymmetric -- if we don't have
187 	 * TX then mask out the peer's RX and vice versa.
188 	 */
189 	if (!(own_cap.cap & IEEE80211_HT_CAP_TX_STBC))
190 		ht_cap.cap &= ~IEEE80211_HT_CAP_RX_STBC;
191 	if (!(own_cap.cap & IEEE80211_HT_CAP_RX_STBC))
192 		ht_cap.cap &= ~IEEE80211_HT_CAP_TX_STBC;
193 
194 	ampdu_info = ht_cap_ie->ampdu_params_info;
195 	ht_cap.ampdu_factor =
196 		ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
197 	ht_cap.ampdu_density =
198 		(ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
199 
200 	/* own MCS TX capabilities */
201 	tx_mcs_set_cap = own_cap.mcs.tx_params;
202 
203 	/* Copy peer MCS TX capabilities, the driver might need them. */
204 	ht_cap.mcs.tx_params = ht_cap_ie->mcs.tx_params;
205 
206 	/* can we TX with MCS rates? */
207 	if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
208 		goto apply;
209 
210 	/* Counting from 0, therefore +1 */
211 	if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
212 		max_tx_streams =
213 			((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
214 				>> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
215 	else
216 		max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
217 
218 	/*
219 	 * 802.11n-2009 20.3.5 / 20.6 says:
220 	 * - indices 0 to 7 and 32 are single spatial stream
221 	 * - 8 to 31 are multiple spatial streams using equal modulation
222 	 *   [8..15 for two streams, 16..23 for three and 24..31 for four]
223 	 * - remainder are multiple spatial streams using unequal modulation
224 	 */
225 	for (i = 0; i < max_tx_streams; i++)
226 		ht_cap.mcs.rx_mask[i] =
227 			own_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
228 
229 	if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
230 		for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
231 		     i < IEEE80211_HT_MCS_MASK_LEN; i++)
232 			ht_cap.mcs.rx_mask[i] =
233 				own_cap.mcs.rx_mask[i] &
234 					ht_cap_ie->mcs.rx_mask[i];
235 
236 	/* handle MCS rate 32 too */
237 	if (own_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
238 		ht_cap.mcs.rx_mask[32/8] |= 1;
239 
240 	/* set Rx highest rate */
241 	ht_cap.mcs.rx_highest = ht_cap_ie->mcs.rx_highest;
242 
243 	if (ht_cap.cap & IEEE80211_HT_CAP_MAX_AMSDU)
244 		sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_7935;
245 	else
246 		sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_3839;
247 
248  apply:
249 	changed = memcmp(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
250 
251 	memcpy(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
252 
253 	switch (sdata->vif.bss_conf.chandef.width) {
254 	default:
255 		WARN_ON_ONCE(1);
256 		/* fall through */
257 	case NL80211_CHAN_WIDTH_20_NOHT:
258 	case NL80211_CHAN_WIDTH_20:
259 		bw = IEEE80211_STA_RX_BW_20;
260 		break;
261 	case NL80211_CHAN_WIDTH_40:
262 	case NL80211_CHAN_WIDTH_80:
263 	case NL80211_CHAN_WIDTH_80P80:
264 	case NL80211_CHAN_WIDTH_160:
265 		bw = ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
266 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
267 		break;
268 	}
269 
270 	sta->sta.bandwidth = bw;
271 
272 	sta->cur_max_bandwidth =
273 		ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
274 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
275 
276 	switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS)
277 			>> IEEE80211_HT_CAP_SM_PS_SHIFT) {
278 	case WLAN_HT_CAP_SM_PS_INVALID:
279 	case WLAN_HT_CAP_SM_PS_STATIC:
280 		smps_mode = IEEE80211_SMPS_STATIC;
281 		break;
282 	case WLAN_HT_CAP_SM_PS_DYNAMIC:
283 		smps_mode = IEEE80211_SMPS_DYNAMIC;
284 		break;
285 	case WLAN_HT_CAP_SM_PS_DISABLED:
286 		smps_mode = IEEE80211_SMPS_OFF;
287 		break;
288 	}
289 
290 	if (smps_mode != sta->sta.smps_mode)
291 		changed = true;
292 	sta->sta.smps_mode = smps_mode;
293 
294 	return changed;
295 }
296 
297 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
298 					 enum ieee80211_agg_stop_reason reason)
299 {
300 	int i;
301 
302 	mutex_lock(&sta->ampdu_mlme.mtx);
303 	for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
304 		___ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
305 						WLAN_REASON_QSTA_LEAVE_QBSS,
306 						reason != AGG_STOP_DESTROY_STA &&
307 						reason != AGG_STOP_PEER_REQUEST);
308 
309 	for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
310 		___ieee80211_stop_tx_ba_session(sta, i, reason);
311 	mutex_unlock(&sta->ampdu_mlme.mtx);
312 
313 	/*
314 	 * In case the tear down is part of a reconfigure due to HW restart
315 	 * request, it is possible that the low level driver requested to stop
316 	 * the BA session, so handle it to properly clean tid_tx data.
317 	 */
318 	if(reason == AGG_STOP_DESTROY_STA) {
319 		cancel_work_sync(&sta->ampdu_mlme.work);
320 
321 		mutex_lock(&sta->ampdu_mlme.mtx);
322 		for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
323 			struct tid_ampdu_tx *tid_tx =
324 				rcu_dereference_protected_tid_tx(sta, i);
325 
326 			if (!tid_tx)
327 				continue;
328 
329 			if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
330 				ieee80211_stop_tx_ba_cb(sta, i, tid_tx);
331 		}
332 		mutex_unlock(&sta->ampdu_mlme.mtx);
333 	}
334 }
335 
336 void ieee80211_ba_session_work(struct work_struct *work)
337 {
338 	struct sta_info *sta =
339 		container_of(work, struct sta_info, ampdu_mlme.work);
340 	struct tid_ampdu_tx *tid_tx;
341 	bool blocked;
342 	int tid;
343 
344 	/* When this flag is set, new sessions should be blocked. */
345 	blocked = test_sta_flag(sta, WLAN_STA_BLOCK_BA);
346 
347 	mutex_lock(&sta->ampdu_mlme.mtx);
348 	for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
349 		if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
350 			___ieee80211_stop_rx_ba_session(
351 				sta, tid, WLAN_BACK_RECIPIENT,
352 				WLAN_REASON_QSTA_TIMEOUT, true);
353 
354 		if (test_and_clear_bit(tid,
355 				       sta->ampdu_mlme.tid_rx_stop_requested))
356 			___ieee80211_stop_rx_ba_session(
357 				sta, tid, WLAN_BACK_RECIPIENT,
358 				WLAN_REASON_UNSPECIFIED, true);
359 
360 		if (!blocked &&
361 		    test_and_clear_bit(tid,
362 				       sta->ampdu_mlme.tid_rx_manage_offl))
363 			___ieee80211_start_rx_ba_session(sta, 0, 0, 0, 1, tid,
364 							 IEEE80211_MAX_AMPDU_BUF_HT,
365 							 false, true);
366 
367 		if (test_and_clear_bit(tid + IEEE80211_NUM_TIDS,
368 				       sta->ampdu_mlme.tid_rx_manage_offl))
369 			___ieee80211_stop_rx_ba_session(
370 				sta, tid, WLAN_BACK_RECIPIENT,
371 				0, false);
372 
373 		spin_lock_bh(&sta->lock);
374 
375 		tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
376 		if (!blocked && tid_tx) {
377 			/*
378 			 * Assign it over to the normal tid_tx array
379 			 * where it "goes live".
380 			 */
381 
382 			sta->ampdu_mlme.tid_start_tx[tid] = NULL;
383 			/* could there be a race? */
384 			if (sta->ampdu_mlme.tid_tx[tid])
385 				kfree(tid_tx);
386 			else
387 				ieee80211_assign_tid_tx(sta, tid, tid_tx);
388 			spin_unlock_bh(&sta->lock);
389 
390 			ieee80211_tx_ba_session_handle_start(sta, tid);
391 			continue;
392 		}
393 		spin_unlock_bh(&sta->lock);
394 
395 		tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
396 		if (!tid_tx)
397 			continue;
398 
399 		if (!blocked &&
400 		    test_and_clear_bit(HT_AGG_STATE_START_CB, &tid_tx->state))
401 			ieee80211_start_tx_ba_cb(sta, tid, tid_tx);
402 		if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
403 			___ieee80211_stop_tx_ba_session(sta, tid,
404 							AGG_STOP_LOCAL_REQUEST);
405 		if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
406 			ieee80211_stop_tx_ba_cb(sta, tid, tid_tx);
407 	}
408 	mutex_unlock(&sta->ampdu_mlme.mtx);
409 }
410 
411 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
412 			  const u8 *da, u16 tid,
413 			  u16 initiator, u16 reason_code)
414 {
415 	struct ieee80211_local *local = sdata->local;
416 	struct sk_buff *skb;
417 	struct ieee80211_mgmt *mgmt;
418 	u16 params;
419 
420 	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
421 	if (!skb)
422 		return;
423 
424 	skb_reserve(skb, local->hw.extra_tx_headroom);
425 	mgmt = skb_put_zero(skb, 24);
426 	memcpy(mgmt->da, da, ETH_ALEN);
427 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
428 	if (sdata->vif.type == NL80211_IFTYPE_AP ||
429 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
430 	    sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
431 		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
432 	else if (sdata->vif.type == NL80211_IFTYPE_STATION)
433 		memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
434 	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
435 		memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
436 
437 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
438 					  IEEE80211_STYPE_ACTION);
439 
440 	skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
441 
442 	mgmt->u.action.category = WLAN_CATEGORY_BACK;
443 	mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
444 	params = (u16)(initiator << 11); 	/* bit 11 initiator */
445 	params |= (u16)(tid << 12); 		/* bit 15:12 TID number */
446 
447 	mgmt->u.action.u.delba.params = cpu_to_le16(params);
448 	mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
449 
450 	ieee80211_tx_skb(sdata, skb);
451 }
452 
453 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
454 			     struct sta_info *sta,
455 			     struct ieee80211_mgmt *mgmt, size_t len)
456 {
457 	u16 tid, params;
458 	u16 initiator;
459 
460 	params = le16_to_cpu(mgmt->u.action.u.delba.params);
461 	tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
462 	initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
463 
464 	ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n",
465 			   mgmt->sa, initiator ? "initiator" : "recipient",
466 			   tid,
467 			   le16_to_cpu(mgmt->u.action.u.delba.reason_code));
468 
469 	if (initiator == WLAN_BACK_INITIATOR)
470 		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
471 					       true);
472 	else
473 		__ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
474 }
475 
476 enum nl80211_smps_mode
477 ieee80211_smps_mode_to_smps_mode(enum ieee80211_smps_mode smps)
478 {
479 	switch (smps) {
480 	case IEEE80211_SMPS_OFF:
481 		return NL80211_SMPS_OFF;
482 	case IEEE80211_SMPS_STATIC:
483 		return NL80211_SMPS_STATIC;
484 	case IEEE80211_SMPS_DYNAMIC:
485 		return NL80211_SMPS_DYNAMIC;
486 	default:
487 		return NL80211_SMPS_OFF;
488 	}
489 }
490 
491 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
492 			       enum ieee80211_smps_mode smps, const u8 *da,
493 			       const u8 *bssid)
494 {
495 	struct ieee80211_local *local = sdata->local;
496 	struct sk_buff *skb;
497 	struct ieee80211_mgmt *action_frame;
498 
499 	/* 27 = header + category + action + smps mode */
500 	skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
501 	if (!skb)
502 		return -ENOMEM;
503 
504 	skb_reserve(skb, local->hw.extra_tx_headroom);
505 	action_frame = skb_put(skb, 27);
506 	memcpy(action_frame->da, da, ETH_ALEN);
507 	memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
508 	memcpy(action_frame->bssid, bssid, ETH_ALEN);
509 	action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
510 						  IEEE80211_STYPE_ACTION);
511 	action_frame->u.action.category = WLAN_CATEGORY_HT;
512 	action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
513 	switch (smps) {
514 	case IEEE80211_SMPS_AUTOMATIC:
515 	case IEEE80211_SMPS_NUM_MODES:
516 		WARN_ON(1);
517 		/* fall through */
518 	case IEEE80211_SMPS_OFF:
519 		action_frame->u.action.u.ht_smps.smps_control =
520 				WLAN_HT_SMPS_CONTROL_DISABLED;
521 		break;
522 	case IEEE80211_SMPS_STATIC:
523 		action_frame->u.action.u.ht_smps.smps_control =
524 				WLAN_HT_SMPS_CONTROL_STATIC;
525 		break;
526 	case IEEE80211_SMPS_DYNAMIC:
527 		action_frame->u.action.u.ht_smps.smps_control =
528 				WLAN_HT_SMPS_CONTROL_DYNAMIC;
529 		break;
530 	}
531 
532 	/* we'll do more on status of this frame */
533 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
534 	ieee80211_tx_skb(sdata, skb);
535 
536 	return 0;
537 }
538 
539 void ieee80211_request_smps_mgd_work(struct work_struct *work)
540 {
541 	struct ieee80211_sub_if_data *sdata =
542 		container_of(work, struct ieee80211_sub_if_data,
543 			     u.mgd.request_smps_work);
544 
545 	sdata_lock(sdata);
546 	__ieee80211_request_smps_mgd(sdata, sdata->u.mgd.driver_smps_mode);
547 	sdata_unlock(sdata);
548 }
549 
550 void ieee80211_request_smps_ap_work(struct work_struct *work)
551 {
552 	struct ieee80211_sub_if_data *sdata =
553 		container_of(work, struct ieee80211_sub_if_data,
554 			     u.ap.request_smps_work);
555 
556 	sdata_lock(sdata);
557 	if (sdata_dereference(sdata->u.ap.beacon, sdata))
558 		__ieee80211_request_smps_ap(sdata,
559 					    sdata->u.ap.driver_smps_mode);
560 	sdata_unlock(sdata);
561 }
562 
563 void ieee80211_request_smps(struct ieee80211_vif *vif,
564 			    enum ieee80211_smps_mode smps_mode)
565 {
566 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
567 
568 	if (WARN_ON_ONCE(vif->type != NL80211_IFTYPE_STATION &&
569 			 vif->type != NL80211_IFTYPE_AP))
570 		return;
571 
572 	if (vif->type == NL80211_IFTYPE_STATION) {
573 		if (sdata->u.mgd.driver_smps_mode == smps_mode)
574 			return;
575 		sdata->u.mgd.driver_smps_mode = smps_mode;
576 		ieee80211_queue_work(&sdata->local->hw,
577 				     &sdata->u.mgd.request_smps_work);
578 	} else {
579 		/* AUTOMATIC is meaningless in AP mode */
580 		if (WARN_ON_ONCE(smps_mode == IEEE80211_SMPS_AUTOMATIC))
581 			return;
582 		if (sdata->u.ap.driver_smps_mode == smps_mode)
583 			return;
584 		sdata->u.ap.driver_smps_mode = smps_mode;
585 		ieee80211_queue_work(&sdata->local->hw,
586 				     &sdata->u.ap.request_smps_work);
587 	}
588 }
589 /* this might change ... don't want non-open drivers using it */
590 EXPORT_SYMBOL_GPL(ieee80211_request_smps);
591