xref: /openbmc/linux/net/mac80211/ht.c (revision 8795a739)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HT handling
4  *
5  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6  * Copyright 2002-2005, Instant802 Networks, Inc.
7  * Copyright 2005-2006, Devicescape Software, Inc.
8  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
9  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10  * Copyright 2007-2010, Intel Corporation
11  * Copyright 2017	Intel Deutschland GmbH
12  */
13 
14 #include <linux/ieee80211.h>
15 #include <linux/export.h>
16 #include <net/mac80211.h>
17 #include "ieee80211_i.h"
18 #include "rate.h"
19 
20 static void __check_htcap_disable(struct ieee80211_ht_cap *ht_capa,
21 				  struct ieee80211_ht_cap *ht_capa_mask,
22 				  struct ieee80211_sta_ht_cap *ht_cap,
23 				  u16 flag)
24 {
25 	__le16 le_flag = cpu_to_le16(flag);
26 	if (ht_capa_mask->cap_info & le_flag) {
27 		if (!(ht_capa->cap_info & le_flag))
28 			ht_cap->cap &= ~flag;
29 	}
30 }
31 
32 static void __check_htcap_enable(struct ieee80211_ht_cap *ht_capa,
33 				  struct ieee80211_ht_cap *ht_capa_mask,
34 				  struct ieee80211_sta_ht_cap *ht_cap,
35 				  u16 flag)
36 {
37 	__le16 le_flag = cpu_to_le16(flag);
38 
39 	if ((ht_capa_mask->cap_info & le_flag) &&
40 	    (ht_capa->cap_info & le_flag))
41 		ht_cap->cap |= flag;
42 }
43 
44 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
45 				     struct ieee80211_sta_ht_cap *ht_cap)
46 {
47 	struct ieee80211_ht_cap *ht_capa, *ht_capa_mask;
48 	u8 *scaps, *smask;
49 	int i;
50 
51 	if (!ht_cap->ht_supported)
52 		return;
53 
54 	switch (sdata->vif.type) {
55 	case NL80211_IFTYPE_STATION:
56 		ht_capa = &sdata->u.mgd.ht_capa;
57 		ht_capa_mask = &sdata->u.mgd.ht_capa_mask;
58 		break;
59 	case NL80211_IFTYPE_ADHOC:
60 		ht_capa = &sdata->u.ibss.ht_capa;
61 		ht_capa_mask = &sdata->u.ibss.ht_capa_mask;
62 		break;
63 	default:
64 		WARN_ON_ONCE(1);
65 		return;
66 	}
67 
68 	scaps = (u8 *)(&ht_capa->mcs.rx_mask);
69 	smask = (u8 *)(&ht_capa_mask->mcs.rx_mask);
70 
71 	/* NOTE:  If you add more over-rides here, update register_hw
72 	 * ht_capa_mod_mask logic in main.c as well.
73 	 * And, if this method can ever change ht_cap.ht_supported, fix
74 	 * the check in ieee80211_add_ht_ie.
75 	 */
76 
77 	/* check for HT over-rides, MCS rates first. */
78 	for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
79 		u8 m = smask[i];
80 		ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
81 		/* Add back rates that are supported */
82 		ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
83 	}
84 
85 	/* Force removal of HT-40 capabilities? */
86 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
87 			      IEEE80211_HT_CAP_SUP_WIDTH_20_40);
88 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
89 			      IEEE80211_HT_CAP_SGI_40);
90 
91 	/* Allow user to disable SGI-20 (SGI-40 is handled above) */
92 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
93 			      IEEE80211_HT_CAP_SGI_20);
94 
95 	/* Allow user to disable the max-AMSDU bit. */
96 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
97 			      IEEE80211_HT_CAP_MAX_AMSDU);
98 
99 	/* Allow user to disable LDPC */
100 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
101 			      IEEE80211_HT_CAP_LDPC_CODING);
102 
103 	/* Allow user to enable 40 MHz intolerant bit. */
104 	__check_htcap_enable(ht_capa, ht_capa_mask, ht_cap,
105 			     IEEE80211_HT_CAP_40MHZ_INTOLERANT);
106 
107 	/* Allow user to enable TX STBC bit  */
108 	__check_htcap_enable(ht_capa, ht_capa_mask, ht_cap,
109 			     IEEE80211_HT_CAP_TX_STBC);
110 
111 	/* Allow user to configure RX STBC bits */
112 	if (ht_capa_mask->cap_info & cpu_to_le16(IEEE80211_HT_CAP_RX_STBC))
113 		ht_cap->cap |= le16_to_cpu(ht_capa->cap_info) &
114 					IEEE80211_HT_CAP_RX_STBC;
115 
116 	/* Allow user to decrease AMPDU factor */
117 	if (ht_capa_mask->ampdu_params_info &
118 	    IEEE80211_HT_AMPDU_PARM_FACTOR) {
119 		u8 n = ht_capa->ampdu_params_info &
120 		       IEEE80211_HT_AMPDU_PARM_FACTOR;
121 		if (n < ht_cap->ampdu_factor)
122 			ht_cap->ampdu_factor = n;
123 	}
124 
125 	/* Allow the user to increase AMPDU density. */
126 	if (ht_capa_mask->ampdu_params_info &
127 	    IEEE80211_HT_AMPDU_PARM_DENSITY) {
128 		u8 n = (ht_capa->ampdu_params_info &
129 			IEEE80211_HT_AMPDU_PARM_DENSITY)
130 			>> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
131 		if (n > ht_cap->ampdu_density)
132 			ht_cap->ampdu_density = n;
133 	}
134 }
135 
136 
137 bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
138 				       struct ieee80211_supported_band *sband,
139 				       const struct ieee80211_ht_cap *ht_cap_ie,
140 				       struct sta_info *sta)
141 {
142 	struct ieee80211_sta_ht_cap ht_cap, own_cap;
143 	u8 ampdu_info, tx_mcs_set_cap;
144 	int i, max_tx_streams;
145 	bool changed;
146 	enum ieee80211_sta_rx_bandwidth bw;
147 	enum ieee80211_smps_mode smps_mode;
148 
149 	memset(&ht_cap, 0, sizeof(ht_cap));
150 
151 	if (!ht_cap_ie || !sband->ht_cap.ht_supported)
152 		goto apply;
153 
154 	ht_cap.ht_supported = true;
155 
156 	own_cap = sband->ht_cap;
157 
158 	/*
159 	 * If user has specified capability over-rides, take care
160 	 * of that if the station we're setting up is the AP or TDLS peer that
161 	 * we advertised a restricted capability set to. Override
162 	 * our own capabilities and then use those below.
163 	 */
164 	if (sdata->vif.type == NL80211_IFTYPE_STATION ||
165 	    sdata->vif.type == NL80211_IFTYPE_ADHOC)
166 		ieee80211_apply_htcap_overrides(sdata, &own_cap);
167 
168 	/*
169 	 * The bits listed in this expression should be
170 	 * the same for the peer and us, if the station
171 	 * advertises more then we can't use those thus
172 	 * we mask them out.
173 	 */
174 	ht_cap.cap = le16_to_cpu(ht_cap_ie->cap_info) &
175 		(own_cap.cap | ~(IEEE80211_HT_CAP_LDPC_CODING |
176 				 IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
177 				 IEEE80211_HT_CAP_GRN_FLD |
178 				 IEEE80211_HT_CAP_SGI_20 |
179 				 IEEE80211_HT_CAP_SGI_40 |
180 				 IEEE80211_HT_CAP_DSSSCCK40));
181 
182 	/*
183 	 * The STBC bits are asymmetric -- if we don't have
184 	 * TX then mask out the peer's RX and vice versa.
185 	 */
186 	if (!(own_cap.cap & IEEE80211_HT_CAP_TX_STBC))
187 		ht_cap.cap &= ~IEEE80211_HT_CAP_RX_STBC;
188 	if (!(own_cap.cap & IEEE80211_HT_CAP_RX_STBC))
189 		ht_cap.cap &= ~IEEE80211_HT_CAP_TX_STBC;
190 
191 	ampdu_info = ht_cap_ie->ampdu_params_info;
192 	ht_cap.ampdu_factor =
193 		ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
194 	ht_cap.ampdu_density =
195 		(ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
196 
197 	/* own MCS TX capabilities */
198 	tx_mcs_set_cap = own_cap.mcs.tx_params;
199 
200 	/* Copy peer MCS TX capabilities, the driver might need them. */
201 	ht_cap.mcs.tx_params = ht_cap_ie->mcs.tx_params;
202 
203 	/* can we TX with MCS rates? */
204 	if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
205 		goto apply;
206 
207 	/* Counting from 0, therefore +1 */
208 	if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
209 		max_tx_streams =
210 			((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
211 				>> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
212 	else
213 		max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
214 
215 	/*
216 	 * 802.11n-2009 20.3.5 / 20.6 says:
217 	 * - indices 0 to 7 and 32 are single spatial stream
218 	 * - 8 to 31 are multiple spatial streams using equal modulation
219 	 *   [8..15 for two streams, 16..23 for three and 24..31 for four]
220 	 * - remainder are multiple spatial streams using unequal modulation
221 	 */
222 	for (i = 0; i < max_tx_streams; i++)
223 		ht_cap.mcs.rx_mask[i] =
224 			own_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
225 
226 	if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
227 		for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
228 		     i < IEEE80211_HT_MCS_MASK_LEN; i++)
229 			ht_cap.mcs.rx_mask[i] =
230 				own_cap.mcs.rx_mask[i] &
231 					ht_cap_ie->mcs.rx_mask[i];
232 
233 	/* handle MCS rate 32 too */
234 	if (own_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
235 		ht_cap.mcs.rx_mask[32/8] |= 1;
236 
237 	/* set Rx highest rate */
238 	ht_cap.mcs.rx_highest = ht_cap_ie->mcs.rx_highest;
239 
240 	if (ht_cap.cap & IEEE80211_HT_CAP_MAX_AMSDU)
241 		sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_7935;
242 	else
243 		sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_3839;
244 
245  apply:
246 	changed = memcmp(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
247 
248 	memcpy(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
249 
250 	switch (sdata->vif.bss_conf.chandef.width) {
251 	default:
252 		WARN_ON_ONCE(1);
253 		/* fall through */
254 	case NL80211_CHAN_WIDTH_20_NOHT:
255 	case NL80211_CHAN_WIDTH_20:
256 		bw = IEEE80211_STA_RX_BW_20;
257 		break;
258 	case NL80211_CHAN_WIDTH_40:
259 	case NL80211_CHAN_WIDTH_80:
260 	case NL80211_CHAN_WIDTH_80P80:
261 	case NL80211_CHAN_WIDTH_160:
262 		bw = ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
263 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
264 		break;
265 	}
266 
267 	sta->sta.bandwidth = bw;
268 
269 	sta->cur_max_bandwidth =
270 		ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
271 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
272 
273 	switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS)
274 			>> IEEE80211_HT_CAP_SM_PS_SHIFT) {
275 	case WLAN_HT_CAP_SM_PS_INVALID:
276 	case WLAN_HT_CAP_SM_PS_STATIC:
277 		smps_mode = IEEE80211_SMPS_STATIC;
278 		break;
279 	case WLAN_HT_CAP_SM_PS_DYNAMIC:
280 		smps_mode = IEEE80211_SMPS_DYNAMIC;
281 		break;
282 	case WLAN_HT_CAP_SM_PS_DISABLED:
283 		smps_mode = IEEE80211_SMPS_OFF;
284 		break;
285 	}
286 
287 	if (smps_mode != sta->sta.smps_mode)
288 		changed = true;
289 	sta->sta.smps_mode = smps_mode;
290 
291 	return changed;
292 }
293 
294 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
295 					 enum ieee80211_agg_stop_reason reason)
296 {
297 	int i;
298 
299 	mutex_lock(&sta->ampdu_mlme.mtx);
300 	for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
301 		___ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
302 						WLAN_REASON_QSTA_LEAVE_QBSS,
303 						reason != AGG_STOP_DESTROY_STA &&
304 						reason != AGG_STOP_PEER_REQUEST);
305 
306 	for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
307 		___ieee80211_stop_tx_ba_session(sta, i, reason);
308 	mutex_unlock(&sta->ampdu_mlme.mtx);
309 
310 	/*
311 	 * In case the tear down is part of a reconfigure due to HW restart
312 	 * request, it is possible that the low level driver requested to stop
313 	 * the BA session, so handle it to properly clean tid_tx data.
314 	 */
315 	if(reason == AGG_STOP_DESTROY_STA) {
316 		cancel_work_sync(&sta->ampdu_mlme.work);
317 
318 		mutex_lock(&sta->ampdu_mlme.mtx);
319 		for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
320 			struct tid_ampdu_tx *tid_tx =
321 				rcu_dereference_protected_tid_tx(sta, i);
322 
323 			if (!tid_tx)
324 				continue;
325 
326 			if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
327 				ieee80211_stop_tx_ba_cb(sta, i, tid_tx);
328 		}
329 		mutex_unlock(&sta->ampdu_mlme.mtx);
330 	}
331 }
332 
333 void ieee80211_ba_session_work(struct work_struct *work)
334 {
335 	struct sta_info *sta =
336 		container_of(work, struct sta_info, ampdu_mlme.work);
337 	struct tid_ampdu_tx *tid_tx;
338 	bool blocked;
339 	int tid;
340 
341 	/* When this flag is set, new sessions should be blocked. */
342 	blocked = test_sta_flag(sta, WLAN_STA_BLOCK_BA);
343 
344 	mutex_lock(&sta->ampdu_mlme.mtx);
345 	for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
346 		if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
347 			___ieee80211_stop_rx_ba_session(
348 				sta, tid, WLAN_BACK_RECIPIENT,
349 				WLAN_REASON_QSTA_TIMEOUT, true);
350 
351 		if (test_and_clear_bit(tid,
352 				       sta->ampdu_mlme.tid_rx_stop_requested))
353 			___ieee80211_stop_rx_ba_session(
354 				sta, tid, WLAN_BACK_RECIPIENT,
355 				WLAN_REASON_UNSPECIFIED, true);
356 
357 		if (!blocked &&
358 		    test_and_clear_bit(tid,
359 				       sta->ampdu_mlme.tid_rx_manage_offl))
360 			___ieee80211_start_rx_ba_session(sta, 0, 0, 0, 1, tid,
361 							 IEEE80211_MAX_AMPDU_BUF_HT,
362 							 false, true, NULL);
363 
364 		if (test_and_clear_bit(tid + IEEE80211_NUM_TIDS,
365 				       sta->ampdu_mlme.tid_rx_manage_offl))
366 			___ieee80211_stop_rx_ba_session(
367 				sta, tid, WLAN_BACK_RECIPIENT,
368 				0, false);
369 
370 		spin_lock_bh(&sta->lock);
371 
372 		tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
373 		if (!blocked && tid_tx) {
374 			/*
375 			 * Assign it over to the normal tid_tx array
376 			 * where it "goes live".
377 			 */
378 
379 			sta->ampdu_mlme.tid_start_tx[tid] = NULL;
380 			/* could there be a race? */
381 			if (sta->ampdu_mlme.tid_tx[tid])
382 				kfree(tid_tx);
383 			else
384 				ieee80211_assign_tid_tx(sta, tid, tid_tx);
385 			spin_unlock_bh(&sta->lock);
386 
387 			ieee80211_tx_ba_session_handle_start(sta, tid);
388 			continue;
389 		}
390 		spin_unlock_bh(&sta->lock);
391 
392 		tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
393 		if (!tid_tx)
394 			continue;
395 
396 		if (!blocked &&
397 		    test_and_clear_bit(HT_AGG_STATE_START_CB, &tid_tx->state))
398 			ieee80211_start_tx_ba_cb(sta, tid, tid_tx);
399 		if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
400 			___ieee80211_stop_tx_ba_session(sta, tid,
401 							AGG_STOP_LOCAL_REQUEST);
402 		if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
403 			ieee80211_stop_tx_ba_cb(sta, tid, tid_tx);
404 	}
405 	mutex_unlock(&sta->ampdu_mlme.mtx);
406 }
407 
408 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
409 			  const u8 *da, u16 tid,
410 			  u16 initiator, u16 reason_code)
411 {
412 	struct ieee80211_local *local = sdata->local;
413 	struct sk_buff *skb;
414 	struct ieee80211_mgmt *mgmt;
415 	u16 params;
416 
417 	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
418 	if (!skb)
419 		return;
420 
421 	skb_reserve(skb, local->hw.extra_tx_headroom);
422 	mgmt = skb_put_zero(skb, 24);
423 	memcpy(mgmt->da, da, ETH_ALEN);
424 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
425 	if (sdata->vif.type == NL80211_IFTYPE_AP ||
426 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
427 	    sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
428 		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
429 	else if (sdata->vif.type == NL80211_IFTYPE_STATION)
430 		memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
431 	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
432 		memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
433 
434 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
435 					  IEEE80211_STYPE_ACTION);
436 
437 	skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
438 
439 	mgmt->u.action.category = WLAN_CATEGORY_BACK;
440 	mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
441 	params = (u16)(initiator << 11); 	/* bit 11 initiator */
442 	params |= (u16)(tid << 12); 		/* bit 15:12 TID number */
443 
444 	mgmt->u.action.u.delba.params = cpu_to_le16(params);
445 	mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
446 
447 	ieee80211_tx_skb(sdata, skb);
448 }
449 
450 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
451 			     struct sta_info *sta,
452 			     struct ieee80211_mgmt *mgmt, size_t len)
453 {
454 	u16 tid, params;
455 	u16 initiator;
456 
457 	params = le16_to_cpu(mgmt->u.action.u.delba.params);
458 	tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
459 	initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
460 
461 	ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n",
462 			   mgmt->sa, initiator ? "initiator" : "recipient",
463 			   tid,
464 			   le16_to_cpu(mgmt->u.action.u.delba.reason_code));
465 
466 	if (initiator == WLAN_BACK_INITIATOR)
467 		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
468 					       true);
469 	else
470 		__ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
471 }
472 
473 enum nl80211_smps_mode
474 ieee80211_smps_mode_to_smps_mode(enum ieee80211_smps_mode smps)
475 {
476 	switch (smps) {
477 	case IEEE80211_SMPS_OFF:
478 		return NL80211_SMPS_OFF;
479 	case IEEE80211_SMPS_STATIC:
480 		return NL80211_SMPS_STATIC;
481 	case IEEE80211_SMPS_DYNAMIC:
482 		return NL80211_SMPS_DYNAMIC;
483 	default:
484 		return NL80211_SMPS_OFF;
485 	}
486 }
487 
488 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
489 			       enum ieee80211_smps_mode smps, const u8 *da,
490 			       const u8 *bssid)
491 {
492 	struct ieee80211_local *local = sdata->local;
493 	struct sk_buff *skb;
494 	struct ieee80211_mgmt *action_frame;
495 
496 	/* 27 = header + category + action + smps mode */
497 	skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
498 	if (!skb)
499 		return -ENOMEM;
500 
501 	skb_reserve(skb, local->hw.extra_tx_headroom);
502 	action_frame = skb_put(skb, 27);
503 	memcpy(action_frame->da, da, ETH_ALEN);
504 	memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
505 	memcpy(action_frame->bssid, bssid, ETH_ALEN);
506 	action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
507 						  IEEE80211_STYPE_ACTION);
508 	action_frame->u.action.category = WLAN_CATEGORY_HT;
509 	action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
510 	switch (smps) {
511 	case IEEE80211_SMPS_AUTOMATIC:
512 	case IEEE80211_SMPS_NUM_MODES:
513 		WARN_ON(1);
514 		/* fall through */
515 	case IEEE80211_SMPS_OFF:
516 		action_frame->u.action.u.ht_smps.smps_control =
517 				WLAN_HT_SMPS_CONTROL_DISABLED;
518 		break;
519 	case IEEE80211_SMPS_STATIC:
520 		action_frame->u.action.u.ht_smps.smps_control =
521 				WLAN_HT_SMPS_CONTROL_STATIC;
522 		break;
523 	case IEEE80211_SMPS_DYNAMIC:
524 		action_frame->u.action.u.ht_smps.smps_control =
525 				WLAN_HT_SMPS_CONTROL_DYNAMIC;
526 		break;
527 	}
528 
529 	/* we'll do more on status of this frame */
530 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
531 	ieee80211_tx_skb(sdata, skb);
532 
533 	return 0;
534 }
535 
536 void ieee80211_request_smps_mgd_work(struct work_struct *work)
537 {
538 	struct ieee80211_sub_if_data *sdata =
539 		container_of(work, struct ieee80211_sub_if_data,
540 			     u.mgd.request_smps_work);
541 
542 	sdata_lock(sdata);
543 	__ieee80211_request_smps_mgd(sdata, sdata->u.mgd.driver_smps_mode);
544 	sdata_unlock(sdata);
545 }
546 
547 void ieee80211_request_smps_ap_work(struct work_struct *work)
548 {
549 	struct ieee80211_sub_if_data *sdata =
550 		container_of(work, struct ieee80211_sub_if_data,
551 			     u.ap.request_smps_work);
552 
553 	sdata_lock(sdata);
554 	if (sdata_dereference(sdata->u.ap.beacon, sdata))
555 		__ieee80211_request_smps_ap(sdata,
556 					    sdata->u.ap.driver_smps_mode);
557 	sdata_unlock(sdata);
558 }
559 
560 void ieee80211_request_smps(struct ieee80211_vif *vif,
561 			    enum ieee80211_smps_mode smps_mode)
562 {
563 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
564 
565 	if (WARN_ON_ONCE(vif->type != NL80211_IFTYPE_STATION &&
566 			 vif->type != NL80211_IFTYPE_AP))
567 		return;
568 
569 	if (vif->type == NL80211_IFTYPE_STATION) {
570 		if (sdata->u.mgd.driver_smps_mode == smps_mode)
571 			return;
572 		sdata->u.mgd.driver_smps_mode = smps_mode;
573 		ieee80211_queue_work(&sdata->local->hw,
574 				     &sdata->u.mgd.request_smps_work);
575 	} else {
576 		/* AUTOMATIC is meaningless in AP mode */
577 		if (WARN_ON_ONCE(smps_mode == IEEE80211_SMPS_AUTOMATIC))
578 			return;
579 		if (sdata->u.ap.driver_smps_mode == smps_mode)
580 			return;
581 		sdata->u.ap.driver_smps_mode = smps_mode;
582 		ieee80211_queue_work(&sdata->local->hw,
583 				     &sdata->u.ap.request_smps_work);
584 	}
585 }
586 /* this might change ... don't want non-open drivers using it */
587 EXPORT_SYMBOL_GPL(ieee80211_request_smps);
588