xref: /openbmc/linux/net/mac80211/ht.c (revision 8440bb9b)
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 & IEEE80211_HT_CAP_RX_STBC)
116 		ht_cap->cap |= ht_capa->cap_info & IEEE80211_HT_CAP_RX_STBC;
117 
118 	/* Allow user to decrease AMPDU factor */
119 	if (ht_capa_mask->ampdu_params_info &
120 	    IEEE80211_HT_AMPDU_PARM_FACTOR) {
121 		u8 n = ht_capa->ampdu_params_info &
122 		       IEEE80211_HT_AMPDU_PARM_FACTOR;
123 		if (n < ht_cap->ampdu_factor)
124 			ht_cap->ampdu_factor = n;
125 	}
126 
127 	/* Allow the user to increase AMPDU density. */
128 	if (ht_capa_mask->ampdu_params_info &
129 	    IEEE80211_HT_AMPDU_PARM_DENSITY) {
130 		u8 n = (ht_capa->ampdu_params_info &
131 			IEEE80211_HT_AMPDU_PARM_DENSITY)
132 			>> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
133 		if (n > ht_cap->ampdu_density)
134 			ht_cap->ampdu_density = n;
135 	}
136 }
137 
138 
139 bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
140 				       struct ieee80211_supported_band *sband,
141 				       const struct ieee80211_ht_cap *ht_cap_ie,
142 				       struct sta_info *sta)
143 {
144 	struct ieee80211_sta_ht_cap ht_cap, own_cap;
145 	u8 ampdu_info, tx_mcs_set_cap;
146 	int i, max_tx_streams;
147 	bool changed;
148 	enum ieee80211_sta_rx_bandwidth bw;
149 	enum ieee80211_smps_mode smps_mode;
150 
151 	memset(&ht_cap, 0, sizeof(ht_cap));
152 
153 	if (!ht_cap_ie || !sband->ht_cap.ht_supported)
154 		goto apply;
155 
156 	ht_cap.ht_supported = true;
157 
158 	own_cap = sband->ht_cap;
159 
160 	/*
161 	 * If user has specified capability over-rides, take care
162 	 * of that if the station we're setting up is the AP or TDLS peer that
163 	 * we advertised a restricted capability set to. Override
164 	 * our own capabilities and then use those below.
165 	 */
166 	if (sdata->vif.type == NL80211_IFTYPE_STATION ||
167 	    sdata->vif.type == NL80211_IFTYPE_ADHOC)
168 		ieee80211_apply_htcap_overrides(sdata, &own_cap);
169 
170 	/*
171 	 * The bits listed in this expression should be
172 	 * the same for the peer and us, if the station
173 	 * advertises more then we can't use those thus
174 	 * we mask them out.
175 	 */
176 	ht_cap.cap = le16_to_cpu(ht_cap_ie->cap_info) &
177 		(own_cap.cap | ~(IEEE80211_HT_CAP_LDPC_CODING |
178 				 IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
179 				 IEEE80211_HT_CAP_GRN_FLD |
180 				 IEEE80211_HT_CAP_SGI_20 |
181 				 IEEE80211_HT_CAP_SGI_40 |
182 				 IEEE80211_HT_CAP_DSSSCCK40));
183 
184 	/*
185 	 * The STBC bits are asymmetric -- if we don't have
186 	 * TX then mask out the peer's RX and vice versa.
187 	 */
188 	if (!(own_cap.cap & IEEE80211_HT_CAP_TX_STBC))
189 		ht_cap.cap &= ~IEEE80211_HT_CAP_RX_STBC;
190 	if (!(own_cap.cap & IEEE80211_HT_CAP_RX_STBC))
191 		ht_cap.cap &= ~IEEE80211_HT_CAP_TX_STBC;
192 
193 	ampdu_info = ht_cap_ie->ampdu_params_info;
194 	ht_cap.ampdu_factor =
195 		ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
196 	ht_cap.ampdu_density =
197 		(ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
198 
199 	/* own MCS TX capabilities */
200 	tx_mcs_set_cap = own_cap.mcs.tx_params;
201 
202 	/* Copy peer MCS TX capabilities, the driver might need them. */
203 	ht_cap.mcs.tx_params = ht_cap_ie->mcs.tx_params;
204 
205 	/* can we TX with MCS rates? */
206 	if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
207 		goto apply;
208 
209 	/* Counting from 0, therefore +1 */
210 	if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
211 		max_tx_streams =
212 			((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
213 				>> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
214 	else
215 		max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
216 
217 	/*
218 	 * 802.11n-2009 20.3.5 / 20.6 says:
219 	 * - indices 0 to 7 and 32 are single spatial stream
220 	 * - 8 to 31 are multiple spatial streams using equal modulation
221 	 *   [8..15 for two streams, 16..23 for three and 24..31 for four]
222 	 * - remainder are multiple spatial streams using unequal modulation
223 	 */
224 	for (i = 0; i < max_tx_streams; i++)
225 		ht_cap.mcs.rx_mask[i] =
226 			own_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
227 
228 	if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
229 		for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
230 		     i < IEEE80211_HT_MCS_MASK_LEN; i++)
231 			ht_cap.mcs.rx_mask[i] =
232 				own_cap.mcs.rx_mask[i] &
233 					ht_cap_ie->mcs.rx_mask[i];
234 
235 	/* handle MCS rate 32 too */
236 	if (own_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
237 		ht_cap.mcs.rx_mask[32/8] |= 1;
238 
239 	/* set Rx highest rate */
240 	ht_cap.mcs.rx_highest = ht_cap_ie->mcs.rx_highest;
241 
242 	if (ht_cap.cap & IEEE80211_HT_CAP_MAX_AMSDU)
243 		sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_7935;
244 	else
245 		sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_3839;
246 
247  apply:
248 	changed = memcmp(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
249 
250 	memcpy(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
251 
252 	switch (sdata->vif.bss_conf.chandef.width) {
253 	default:
254 		WARN_ON_ONCE(1);
255 		/* fall through */
256 	case NL80211_CHAN_WIDTH_20_NOHT:
257 	case NL80211_CHAN_WIDTH_20:
258 		bw = IEEE80211_STA_RX_BW_20;
259 		break;
260 	case NL80211_CHAN_WIDTH_40:
261 	case NL80211_CHAN_WIDTH_80:
262 	case NL80211_CHAN_WIDTH_80P80:
263 	case NL80211_CHAN_WIDTH_160:
264 		bw = ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
265 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
266 		break;
267 	}
268 
269 	sta->sta.bandwidth = bw;
270 
271 	sta->cur_max_bandwidth =
272 		ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
273 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
274 
275 	switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS)
276 			>> IEEE80211_HT_CAP_SM_PS_SHIFT) {
277 	case WLAN_HT_CAP_SM_PS_INVALID:
278 	case WLAN_HT_CAP_SM_PS_STATIC:
279 		smps_mode = IEEE80211_SMPS_STATIC;
280 		break;
281 	case WLAN_HT_CAP_SM_PS_DYNAMIC:
282 		smps_mode = IEEE80211_SMPS_DYNAMIC;
283 		break;
284 	case WLAN_HT_CAP_SM_PS_DISABLED:
285 		smps_mode = IEEE80211_SMPS_OFF;
286 		break;
287 	}
288 
289 	if (smps_mode != sta->sta.smps_mode)
290 		changed = true;
291 	sta->sta.smps_mode = smps_mode;
292 
293 	return changed;
294 }
295 
296 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
297 					 enum ieee80211_agg_stop_reason reason)
298 {
299 	int i;
300 
301 	mutex_lock(&sta->ampdu_mlme.mtx);
302 	for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
303 		___ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
304 						WLAN_REASON_QSTA_LEAVE_QBSS,
305 						reason != AGG_STOP_DESTROY_STA &&
306 						reason != AGG_STOP_PEER_REQUEST);
307 
308 	for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
309 		___ieee80211_stop_tx_ba_session(sta, i, reason);
310 	mutex_unlock(&sta->ampdu_mlme.mtx);
311 
312 	/*
313 	 * In case the tear down is part of a reconfigure due to HW restart
314 	 * request, it is possible that the low level driver requested to stop
315 	 * the BA session, so handle it to properly clean tid_tx data.
316 	 */
317 	if(reason == AGG_STOP_DESTROY_STA) {
318 		cancel_work_sync(&sta->ampdu_mlme.work);
319 
320 		mutex_lock(&sta->ampdu_mlme.mtx);
321 		for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
322 			struct tid_ampdu_tx *tid_tx =
323 				rcu_dereference_protected_tid_tx(sta, i);
324 
325 			if (!tid_tx)
326 				continue;
327 
328 			if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
329 				ieee80211_stop_tx_ba_cb(sta, i, tid_tx);
330 		}
331 		mutex_unlock(&sta->ampdu_mlme.mtx);
332 	}
333 }
334 
335 void ieee80211_ba_session_work(struct work_struct *work)
336 {
337 	struct sta_info *sta =
338 		container_of(work, struct sta_info, ampdu_mlme.work);
339 	struct tid_ampdu_tx *tid_tx;
340 	bool blocked;
341 	int tid;
342 
343 	/* When this flag is set, new sessions should be blocked. */
344 	blocked = test_sta_flag(sta, WLAN_STA_BLOCK_BA);
345 
346 	mutex_lock(&sta->ampdu_mlme.mtx);
347 	for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
348 		if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
349 			___ieee80211_stop_rx_ba_session(
350 				sta, tid, WLAN_BACK_RECIPIENT,
351 				WLAN_REASON_QSTA_TIMEOUT, true);
352 
353 		if (test_and_clear_bit(tid,
354 				       sta->ampdu_mlme.tid_rx_stop_requested))
355 			___ieee80211_stop_rx_ba_session(
356 				sta, tid, WLAN_BACK_RECIPIENT,
357 				WLAN_REASON_UNSPECIFIED, true);
358 
359 		if (!blocked &&
360 		    test_and_clear_bit(tid,
361 				       sta->ampdu_mlme.tid_rx_manage_offl))
362 			___ieee80211_start_rx_ba_session(sta, 0, 0, 0, 1, tid,
363 							 IEEE80211_MAX_AMPDU_BUF_HT,
364 							 false, true);
365 
366 		if (test_and_clear_bit(tid + IEEE80211_NUM_TIDS,
367 				       sta->ampdu_mlme.tid_rx_manage_offl))
368 			___ieee80211_stop_rx_ba_session(
369 				sta, tid, WLAN_BACK_RECIPIENT,
370 				0, false);
371 
372 		spin_lock_bh(&sta->lock);
373 
374 		tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
375 		if (!blocked && tid_tx) {
376 			/*
377 			 * Assign it over to the normal tid_tx array
378 			 * where it "goes live".
379 			 */
380 
381 			sta->ampdu_mlme.tid_start_tx[tid] = NULL;
382 			/* could there be a race? */
383 			if (sta->ampdu_mlme.tid_tx[tid])
384 				kfree(tid_tx);
385 			else
386 				ieee80211_assign_tid_tx(sta, tid, tid_tx);
387 			spin_unlock_bh(&sta->lock);
388 
389 			ieee80211_tx_ba_session_handle_start(sta, tid);
390 			continue;
391 		}
392 		spin_unlock_bh(&sta->lock);
393 
394 		tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
395 		if (!tid_tx)
396 			continue;
397 
398 		if (!blocked &&
399 		    test_and_clear_bit(HT_AGG_STATE_START_CB, &tid_tx->state))
400 			ieee80211_start_tx_ba_cb(sta, tid, tid_tx);
401 		if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
402 			___ieee80211_stop_tx_ba_session(sta, tid,
403 							AGG_STOP_LOCAL_REQUEST);
404 		if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
405 			ieee80211_stop_tx_ba_cb(sta, tid, tid_tx);
406 	}
407 	mutex_unlock(&sta->ampdu_mlme.mtx);
408 }
409 
410 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
411 			  const u8 *da, u16 tid,
412 			  u16 initiator, u16 reason_code)
413 {
414 	struct ieee80211_local *local = sdata->local;
415 	struct sk_buff *skb;
416 	struct ieee80211_mgmt *mgmt;
417 	u16 params;
418 
419 	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
420 	if (!skb)
421 		return;
422 
423 	skb_reserve(skb, local->hw.extra_tx_headroom);
424 	mgmt = skb_put_zero(skb, 24);
425 	memcpy(mgmt->da, da, ETH_ALEN);
426 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
427 	if (sdata->vif.type == NL80211_IFTYPE_AP ||
428 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
429 	    sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
430 		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
431 	else if (sdata->vif.type == NL80211_IFTYPE_STATION)
432 		memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
433 	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
434 		memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
435 
436 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
437 					  IEEE80211_STYPE_ACTION);
438 
439 	skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
440 
441 	mgmt->u.action.category = WLAN_CATEGORY_BACK;
442 	mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
443 	params = (u16)(initiator << 11); 	/* bit 11 initiator */
444 	params |= (u16)(tid << 12); 		/* bit 15:12 TID number */
445 
446 	mgmt->u.action.u.delba.params = cpu_to_le16(params);
447 	mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
448 
449 	ieee80211_tx_skb(sdata, skb);
450 }
451 
452 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
453 			     struct sta_info *sta,
454 			     struct ieee80211_mgmt *mgmt, size_t len)
455 {
456 	u16 tid, params;
457 	u16 initiator;
458 
459 	params = le16_to_cpu(mgmt->u.action.u.delba.params);
460 	tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
461 	initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
462 
463 	ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n",
464 			   mgmt->sa, initiator ? "initiator" : "recipient",
465 			   tid,
466 			   le16_to_cpu(mgmt->u.action.u.delba.reason_code));
467 
468 	if (initiator == WLAN_BACK_INITIATOR)
469 		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
470 					       true);
471 	else
472 		__ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
473 }
474 
475 enum nl80211_smps_mode
476 ieee80211_smps_mode_to_smps_mode(enum ieee80211_smps_mode smps)
477 {
478 	switch (smps) {
479 	case IEEE80211_SMPS_OFF:
480 		return NL80211_SMPS_OFF;
481 	case IEEE80211_SMPS_STATIC:
482 		return NL80211_SMPS_STATIC;
483 	case IEEE80211_SMPS_DYNAMIC:
484 		return NL80211_SMPS_DYNAMIC;
485 	default:
486 		return NL80211_SMPS_OFF;
487 	}
488 }
489 
490 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
491 			       enum ieee80211_smps_mode smps, const u8 *da,
492 			       const u8 *bssid)
493 {
494 	struct ieee80211_local *local = sdata->local;
495 	struct sk_buff *skb;
496 	struct ieee80211_mgmt *action_frame;
497 
498 	/* 27 = header + category + action + smps mode */
499 	skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
500 	if (!skb)
501 		return -ENOMEM;
502 
503 	skb_reserve(skb, local->hw.extra_tx_headroom);
504 	action_frame = skb_put(skb, 27);
505 	memcpy(action_frame->da, da, ETH_ALEN);
506 	memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
507 	memcpy(action_frame->bssid, bssid, ETH_ALEN);
508 	action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
509 						  IEEE80211_STYPE_ACTION);
510 	action_frame->u.action.category = WLAN_CATEGORY_HT;
511 	action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
512 	switch (smps) {
513 	case IEEE80211_SMPS_AUTOMATIC:
514 	case IEEE80211_SMPS_NUM_MODES:
515 		WARN_ON(1);
516 		/* fall through */
517 	case IEEE80211_SMPS_OFF:
518 		action_frame->u.action.u.ht_smps.smps_control =
519 				WLAN_HT_SMPS_CONTROL_DISABLED;
520 		break;
521 	case IEEE80211_SMPS_STATIC:
522 		action_frame->u.action.u.ht_smps.smps_control =
523 				WLAN_HT_SMPS_CONTROL_STATIC;
524 		break;
525 	case IEEE80211_SMPS_DYNAMIC:
526 		action_frame->u.action.u.ht_smps.smps_control =
527 				WLAN_HT_SMPS_CONTROL_DYNAMIC;
528 		break;
529 	}
530 
531 	/* we'll do more on status of this frame */
532 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
533 	ieee80211_tx_skb(sdata, skb);
534 
535 	return 0;
536 }
537 
538 void ieee80211_request_smps_mgd_work(struct work_struct *work)
539 {
540 	struct ieee80211_sub_if_data *sdata =
541 		container_of(work, struct ieee80211_sub_if_data,
542 			     u.mgd.request_smps_work);
543 
544 	sdata_lock(sdata);
545 	__ieee80211_request_smps_mgd(sdata, sdata->u.mgd.driver_smps_mode);
546 	sdata_unlock(sdata);
547 }
548 
549 void ieee80211_request_smps_ap_work(struct work_struct *work)
550 {
551 	struct ieee80211_sub_if_data *sdata =
552 		container_of(work, struct ieee80211_sub_if_data,
553 			     u.ap.request_smps_work);
554 
555 	sdata_lock(sdata);
556 	if (sdata_dereference(sdata->u.ap.beacon, sdata))
557 		__ieee80211_request_smps_ap(sdata,
558 					    sdata->u.ap.driver_smps_mode);
559 	sdata_unlock(sdata);
560 }
561 
562 void ieee80211_request_smps(struct ieee80211_vif *vif,
563 			    enum ieee80211_smps_mode smps_mode)
564 {
565 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
566 
567 	if (WARN_ON_ONCE(vif->type != NL80211_IFTYPE_STATION &&
568 			 vif->type != NL80211_IFTYPE_AP))
569 		return;
570 
571 	if (vif->type == NL80211_IFTYPE_STATION) {
572 		if (sdata->u.mgd.driver_smps_mode == smps_mode)
573 			return;
574 		sdata->u.mgd.driver_smps_mode = smps_mode;
575 		ieee80211_queue_work(&sdata->local->hw,
576 				     &sdata->u.mgd.request_smps_work);
577 	} else {
578 		/* AUTOMATIC is meaningless in AP mode */
579 		if (WARN_ON_ONCE(smps_mode == IEEE80211_SMPS_AUTOMATIC))
580 			return;
581 		if (sdata->u.ap.driver_smps_mode == smps_mode)
582 			return;
583 		sdata->u.ap.driver_smps_mode = smps_mode;
584 		ieee80211_queue_work(&sdata->local->hw,
585 				     &sdata->u.ap.request_smps_work);
586 	}
587 }
588 /* this might change ... don't want non-open drivers using it */
589 EXPORT_SYMBOL_GPL(ieee80211_request_smps);
590