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