xref: /openbmc/linux/net/mac80211/ht.c (revision 63705da3)
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  * Copyright(c) 2020-2021 Intel Corporation
13  */
14 
15 #include <linux/ieee80211.h>
16 #include <linux/export.h>
17 #include <net/mac80211.h>
18 #include "ieee80211_i.h"
19 #include "rate.h"
20 
21 static void __check_htcap_disable(struct ieee80211_ht_cap *ht_capa,
22 				  struct ieee80211_ht_cap *ht_capa_mask,
23 				  struct ieee80211_sta_ht_cap *ht_cap,
24 				  u16 flag)
25 {
26 	__le16 le_flag = cpu_to_le16(flag);
27 	if (ht_capa_mask->cap_info & le_flag) {
28 		if (!(ht_capa->cap_info & le_flag))
29 			ht_cap->cap &= ~flag;
30 	}
31 }
32 
33 static void __check_htcap_enable(struct ieee80211_ht_cap *ht_capa,
34 				  struct ieee80211_ht_cap *ht_capa_mask,
35 				  struct ieee80211_sta_ht_cap *ht_cap,
36 				  u16 flag)
37 {
38 	__le16 le_flag = cpu_to_le16(flag);
39 
40 	if ((ht_capa_mask->cap_info & le_flag) &&
41 	    (ht_capa->cap_info & le_flag))
42 		ht_cap->cap |= flag;
43 }
44 
45 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
46 				     struct ieee80211_sta_ht_cap *ht_cap)
47 {
48 	struct ieee80211_ht_cap *ht_capa, *ht_capa_mask;
49 	u8 *scaps, *smask;
50 	int i;
51 
52 	if (!ht_cap->ht_supported)
53 		return;
54 
55 	switch (sdata->vif.type) {
56 	case NL80211_IFTYPE_STATION:
57 		ht_capa = &sdata->u.mgd.ht_capa;
58 		ht_capa_mask = &sdata->u.mgd.ht_capa_mask;
59 		break;
60 	case NL80211_IFTYPE_ADHOC:
61 		ht_capa = &sdata->u.ibss.ht_capa;
62 		ht_capa_mask = &sdata->u.ibss.ht_capa_mask;
63 		break;
64 	default:
65 		WARN_ON_ONCE(1);
66 		return;
67 	}
68 
69 	scaps = (u8 *)(&ht_capa->mcs.rx_mask);
70 	smask = (u8 *)(&ht_capa_mask->mcs.rx_mask);
71 
72 	/* NOTE:  If you add more over-rides here, update register_hw
73 	 * ht_capa_mod_mask logic in main.c as well.
74 	 * And, if this method can ever change ht_cap.ht_supported, fix
75 	 * the check in ieee80211_add_ht_ie.
76 	 */
77 
78 	/* check for HT over-rides, MCS rates first. */
79 	for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
80 		u8 m = smask[i];
81 		ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
82 		/* Add back rates that are supported */
83 		ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
84 	}
85 
86 	/* Force removal of HT-40 capabilities? */
87 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
88 			      IEEE80211_HT_CAP_SUP_WIDTH_20_40);
89 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
90 			      IEEE80211_HT_CAP_SGI_40);
91 
92 	/* Allow user to disable SGI-20 (SGI-40 is handled above) */
93 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
94 			      IEEE80211_HT_CAP_SGI_20);
95 
96 	/* Allow user to disable the max-AMSDU bit. */
97 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
98 			      IEEE80211_HT_CAP_MAX_AMSDU);
99 
100 	/* Allow user to disable LDPC */
101 	__check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
102 			      IEEE80211_HT_CAP_LDPC_CODING);
103 
104 	/* Allow user to enable 40 MHz intolerant bit. */
105 	__check_htcap_enable(ht_capa, ht_capa_mask, ht_cap,
106 			     IEEE80211_HT_CAP_40MHZ_INTOLERANT);
107 
108 	/* Allow user to enable TX STBC bit  */
109 	__check_htcap_enable(ht_capa, ht_capa_mask, ht_cap,
110 			     IEEE80211_HT_CAP_TX_STBC);
111 
112 	/* Allow user to configure RX STBC bits */
113 	if (ht_capa_mask->cap_info & cpu_to_le16(IEEE80211_HT_CAP_RX_STBC))
114 		ht_cap->cap |= le16_to_cpu(ht_capa->cap_info) &
115 					IEEE80211_HT_CAP_RX_STBC;
116 
117 	/* Allow user to decrease AMPDU factor */
118 	if (ht_capa_mask->ampdu_params_info &
119 	    IEEE80211_HT_AMPDU_PARM_FACTOR) {
120 		u8 n = ht_capa->ampdu_params_info &
121 		       IEEE80211_HT_AMPDU_PARM_FACTOR;
122 		if (n < ht_cap->ampdu_factor)
123 			ht_cap->ampdu_factor = n;
124 	}
125 
126 	/* Allow the user to increase AMPDU density. */
127 	if (ht_capa_mask->ampdu_params_info &
128 	    IEEE80211_HT_AMPDU_PARM_DENSITY) {
129 		u8 n = (ht_capa->ampdu_params_info &
130 			IEEE80211_HT_AMPDU_PARM_DENSITY)
131 			>> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
132 		if (n > ht_cap->ampdu_density)
133 			ht_cap->ampdu_density = n;
134 	}
135 }
136 
137 
138 bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
139 				       struct ieee80211_supported_band *sband,
140 				       const struct ieee80211_ht_cap *ht_cap_ie,
141 				       struct sta_info *sta)
142 {
143 	struct ieee80211_sta_ht_cap ht_cap, own_cap;
144 	u8 ampdu_info, tx_mcs_set_cap;
145 	int i, max_tx_streams;
146 	bool changed;
147 	enum ieee80211_sta_rx_bandwidth bw;
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 		fallthrough;
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 	if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
274 	    sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
275 		enum ieee80211_smps_mode smps_mode;
276 
277 		switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS)
278 				>> IEEE80211_HT_CAP_SM_PS_SHIFT) {
279 		case WLAN_HT_CAP_SM_PS_INVALID:
280 		case WLAN_HT_CAP_SM_PS_STATIC:
281 			smps_mode = IEEE80211_SMPS_STATIC;
282 			break;
283 		case WLAN_HT_CAP_SM_PS_DYNAMIC:
284 			smps_mode = IEEE80211_SMPS_DYNAMIC;
285 			break;
286 		case WLAN_HT_CAP_SM_PS_DISABLED:
287 			smps_mode = IEEE80211_SMPS_OFF;
288 			break;
289 		}
290 
291 		if (smps_mode != sta->sta.smps_mode)
292 			changed = true;
293 		sta->sta.smps_mode = smps_mode;
294 	} else {
295 		sta->sta.smps_mode = IEEE80211_SMPS_OFF;
296 	}
297 	return changed;
298 }
299 
300 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
301 					 enum ieee80211_agg_stop_reason reason)
302 {
303 	int i;
304 
305 	mutex_lock(&sta->ampdu_mlme.mtx);
306 	for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
307 		___ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
308 						WLAN_REASON_QSTA_LEAVE_QBSS,
309 						reason != AGG_STOP_DESTROY_STA &&
310 						reason != AGG_STOP_PEER_REQUEST);
311 
312 	for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
313 		___ieee80211_stop_tx_ba_session(sta, i, reason);
314 	mutex_unlock(&sta->ampdu_mlme.mtx);
315 
316 	/*
317 	 * In case the tear down is part of a reconfigure due to HW restart
318 	 * request, it is possible that the low level driver requested to stop
319 	 * the BA session, so handle it to properly clean tid_tx data.
320 	 */
321 	if(reason == AGG_STOP_DESTROY_STA) {
322 		cancel_work_sync(&sta->ampdu_mlme.work);
323 
324 		mutex_lock(&sta->ampdu_mlme.mtx);
325 		for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
326 			struct tid_ampdu_tx *tid_tx =
327 				rcu_dereference_protected_tid_tx(sta, i);
328 
329 			if (!tid_tx)
330 				continue;
331 
332 			if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
333 				ieee80211_stop_tx_ba_cb(sta, i, tid_tx);
334 		}
335 		mutex_unlock(&sta->ampdu_mlme.mtx);
336 	}
337 }
338 
339 void ieee80211_ba_session_work(struct work_struct *work)
340 {
341 	struct sta_info *sta =
342 		container_of(work, struct sta_info, ampdu_mlme.work);
343 	struct tid_ampdu_tx *tid_tx;
344 	bool blocked;
345 	int tid;
346 
347 	/* When this flag is set, new sessions should be blocked. */
348 	blocked = test_sta_flag(sta, WLAN_STA_BLOCK_BA);
349 
350 	mutex_lock(&sta->ampdu_mlme.mtx);
351 	for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
352 		if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
353 			___ieee80211_stop_rx_ba_session(
354 				sta, tid, WLAN_BACK_RECIPIENT,
355 				WLAN_REASON_QSTA_TIMEOUT, true);
356 
357 		if (test_and_clear_bit(tid,
358 				       sta->ampdu_mlme.tid_rx_stop_requested))
359 			___ieee80211_stop_rx_ba_session(
360 				sta, tid, WLAN_BACK_RECIPIENT,
361 				WLAN_REASON_UNSPECIFIED, true);
362 
363 		if (!blocked &&
364 		    test_and_clear_bit(tid,
365 				       sta->ampdu_mlme.tid_rx_manage_offl))
366 			___ieee80211_start_rx_ba_session(sta, 0, 0, 0, 1, tid,
367 							 IEEE80211_MAX_AMPDU_BUF_HT,
368 							 false, true, NULL);
369 
370 		if (test_and_clear_bit(tid + IEEE80211_NUM_TIDS,
371 				       sta->ampdu_mlme.tid_rx_manage_offl))
372 			___ieee80211_stop_rx_ba_session(
373 				sta, tid, WLAN_BACK_RECIPIENT,
374 				0, false);
375 
376 		spin_lock_bh(&sta->lock);
377 
378 		tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
379 		if (!blocked && tid_tx) {
380 			/*
381 			 * Assign it over to the normal tid_tx array
382 			 * where it "goes live".
383 			 */
384 
385 			sta->ampdu_mlme.tid_start_tx[tid] = NULL;
386 			/* could there be a race? */
387 			if (sta->ampdu_mlme.tid_tx[tid])
388 				kfree(tid_tx);
389 			else
390 				ieee80211_assign_tid_tx(sta, tid, tid_tx);
391 			spin_unlock_bh(&sta->lock);
392 
393 			ieee80211_tx_ba_session_handle_start(sta, tid);
394 			continue;
395 		}
396 		spin_unlock_bh(&sta->lock);
397 
398 		tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
399 		if (!tid_tx)
400 			continue;
401 
402 		if (!blocked &&
403 		    test_and_clear_bit(HT_AGG_STATE_START_CB, &tid_tx->state))
404 			ieee80211_start_tx_ba_cb(sta, tid, tid_tx);
405 		if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
406 			___ieee80211_stop_tx_ba_session(sta, tid,
407 							AGG_STOP_LOCAL_REQUEST);
408 		if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
409 			ieee80211_stop_tx_ba_cb(sta, tid, tid_tx);
410 	}
411 	mutex_unlock(&sta->ampdu_mlme.mtx);
412 }
413 
414 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
415 			  const u8 *da, u16 tid,
416 			  u16 initiator, u16 reason_code)
417 {
418 	struct ieee80211_local *local = sdata->local;
419 	struct sk_buff *skb;
420 	struct ieee80211_mgmt *mgmt;
421 	u16 params;
422 
423 	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
424 	if (!skb)
425 		return;
426 
427 	skb_reserve(skb, local->hw.extra_tx_headroom);
428 	mgmt = skb_put_zero(skb, 24);
429 	memcpy(mgmt->da, da, ETH_ALEN);
430 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
431 	if (sdata->vif.type == NL80211_IFTYPE_AP ||
432 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
433 	    sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
434 		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
435 	else if (sdata->vif.type == NL80211_IFTYPE_STATION)
436 		memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
437 	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
438 		memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
439 
440 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
441 					  IEEE80211_STYPE_ACTION);
442 
443 	skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
444 
445 	mgmt->u.action.category = WLAN_CATEGORY_BACK;
446 	mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
447 	params = (u16)(initiator << 11); 	/* bit 11 initiator */
448 	params |= (u16)(tid << 12); 		/* bit 15:12 TID number */
449 
450 	mgmt->u.action.u.delba.params = cpu_to_le16(params);
451 	mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
452 
453 	ieee80211_tx_skb(sdata, skb);
454 }
455 
456 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
457 			     struct sta_info *sta,
458 			     struct ieee80211_mgmt *mgmt, size_t len)
459 {
460 	u16 tid, params;
461 	u16 initiator;
462 
463 	params = le16_to_cpu(mgmt->u.action.u.delba.params);
464 	tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
465 	initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
466 
467 	ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n",
468 			   mgmt->sa, initiator ? "initiator" : "recipient",
469 			   tid,
470 			   le16_to_cpu(mgmt->u.action.u.delba.reason_code));
471 
472 	if (initiator == WLAN_BACK_INITIATOR)
473 		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
474 					       true);
475 	else
476 		__ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
477 }
478 
479 enum nl80211_smps_mode
480 ieee80211_smps_mode_to_smps_mode(enum ieee80211_smps_mode smps)
481 {
482 	switch (smps) {
483 	case IEEE80211_SMPS_OFF:
484 		return NL80211_SMPS_OFF;
485 	case IEEE80211_SMPS_STATIC:
486 		return NL80211_SMPS_STATIC;
487 	case IEEE80211_SMPS_DYNAMIC:
488 		return NL80211_SMPS_DYNAMIC;
489 	default:
490 		return NL80211_SMPS_OFF;
491 	}
492 }
493 
494 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
495 			       enum ieee80211_smps_mode smps, const u8 *da,
496 			       const u8 *bssid)
497 {
498 	struct ieee80211_local *local = sdata->local;
499 	struct sk_buff *skb;
500 	struct ieee80211_mgmt *action_frame;
501 
502 	/* 27 = header + category + action + smps mode */
503 	skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
504 	if (!skb)
505 		return -ENOMEM;
506 
507 	skb_reserve(skb, local->hw.extra_tx_headroom);
508 	action_frame = skb_put(skb, 27);
509 	memcpy(action_frame->da, da, ETH_ALEN);
510 	memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
511 	memcpy(action_frame->bssid, bssid, ETH_ALEN);
512 	action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
513 						  IEEE80211_STYPE_ACTION);
514 	action_frame->u.action.category = WLAN_CATEGORY_HT;
515 	action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
516 	switch (smps) {
517 	case IEEE80211_SMPS_AUTOMATIC:
518 	case IEEE80211_SMPS_NUM_MODES:
519 		WARN_ON(1);
520 		fallthrough;
521 	case IEEE80211_SMPS_OFF:
522 		action_frame->u.action.u.ht_smps.smps_control =
523 				WLAN_HT_SMPS_CONTROL_DISABLED;
524 		break;
525 	case IEEE80211_SMPS_STATIC:
526 		action_frame->u.action.u.ht_smps.smps_control =
527 				WLAN_HT_SMPS_CONTROL_STATIC;
528 		break;
529 	case IEEE80211_SMPS_DYNAMIC:
530 		action_frame->u.action.u.ht_smps.smps_control =
531 				WLAN_HT_SMPS_CONTROL_DYNAMIC;
532 		break;
533 	}
534 
535 	/* we'll do more on status of this frame */
536 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
537 	ieee80211_tx_skb(sdata, skb);
538 
539 	return 0;
540 }
541 
542 void ieee80211_request_smps_mgd_work(struct work_struct *work)
543 {
544 	struct ieee80211_sub_if_data *sdata =
545 		container_of(work, struct ieee80211_sub_if_data,
546 			     u.mgd.request_smps_work);
547 
548 	sdata_lock(sdata);
549 	__ieee80211_request_smps_mgd(sdata, sdata->u.mgd.driver_smps_mode);
550 	sdata_unlock(sdata);
551 }
552 
553 void ieee80211_request_smps(struct ieee80211_vif *vif,
554 			    enum ieee80211_smps_mode smps_mode)
555 {
556 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
557 
558 	if (WARN_ON_ONCE(vif->type != NL80211_IFTYPE_STATION))
559 		return;
560 
561 	if (sdata->u.mgd.driver_smps_mode == smps_mode)
562 		return;
563 
564 	sdata->u.mgd.driver_smps_mode = smps_mode;
565 	ieee80211_queue_work(&sdata->local->hw,
566 			     &sdata->u.mgd.request_smps_work);
567 }
568 /* this might change ... don't want non-open drivers using it */
569 EXPORT_SYMBOL_GPL(ieee80211_request_smps);
570