ARM: tegra: dvfs: Add interface to set fmax at vmin
[linux-3.10.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  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  */
15
16 #include <linux/ieee80211.h>
17 #include <linux/export.h>
18 #include <net/mac80211.h>
19 #include "ieee80211_i.h"
20 #include "rate.h"
21
22 static void __check_htcap_disable(struct ieee80211_sub_if_data *sdata,
23                                   struct ieee80211_sta_ht_cap *ht_cap,
24                                   u16 flag)
25 {
26         __le16 le_flag = cpu_to_le16(flag);
27         if (sdata->u.mgd.ht_capa_mask.cap_info & le_flag) {
28                 if (!(sdata->u.mgd.ht_capa.cap_info & le_flag))
29                         ht_cap->cap &= ~flag;
30         }
31 }
32
33 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
34                                      struct ieee80211_sta_ht_cap *ht_cap)
35 {
36         u8 *scaps = (u8 *)(&sdata->u.mgd.ht_capa.mcs.rx_mask);
37         u8 *smask = (u8 *)(&sdata->u.mgd.ht_capa_mask.mcs.rx_mask);
38         int i;
39
40         if (!ht_cap->ht_supported)
41                 return;
42
43         /* NOTE:  If you add more over-rides here, update register_hw
44          * ht_capa_mod_msk logic in main.c as well.
45          * And, if this method can ever change ht_cap.ht_supported, fix
46          * the check in ieee80211_add_ht_ie.
47          */
48
49         /* check for HT over-rides, MCS rates first. */
50         for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
51                 u8 m = smask[i];
52                 ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
53                 /* Add back rates that are supported */
54                 ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
55         }
56
57         /* Force removal of HT-40 capabilities? */
58         __check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_SUP_WIDTH_20_40);
59         __check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_SGI_40);
60
61         /* Allow user to disable SGI-20 (SGI-40 is handled above) */
62         __check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_SGI_20);
63
64         /* Allow user to disable the max-AMSDU bit. */
65         __check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_MAX_AMSDU);
66
67         /* Allow user to decrease AMPDU factor */
68         if (sdata->u.mgd.ht_capa_mask.ampdu_params_info &
69             IEEE80211_HT_AMPDU_PARM_FACTOR) {
70                 u8 n = sdata->u.mgd.ht_capa.ampdu_params_info
71                         & IEEE80211_HT_AMPDU_PARM_FACTOR;
72                 if (n < ht_cap->ampdu_factor)
73                         ht_cap->ampdu_factor = n;
74         }
75
76         /* Allow the user to increase AMPDU density. */
77         if (sdata->u.mgd.ht_capa_mask.ampdu_params_info &
78             IEEE80211_HT_AMPDU_PARM_DENSITY) {
79                 u8 n = (sdata->u.mgd.ht_capa.ampdu_params_info &
80                         IEEE80211_HT_AMPDU_PARM_DENSITY)
81                         >> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
82                 if (n > ht_cap->ampdu_density)
83                         ht_cap->ampdu_density = n;
84         }
85 }
86
87
88 bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
89                                        struct ieee80211_supported_band *sband,
90                                        const struct ieee80211_ht_cap *ht_cap_ie,
91                                        struct sta_info *sta)
92 {
93         struct ieee80211_sta_ht_cap ht_cap, own_cap;
94         u8 ampdu_info, tx_mcs_set_cap;
95         int i, max_tx_streams;
96         bool changed;
97         enum ieee80211_sta_rx_bandwidth bw;
98         enum ieee80211_smps_mode smps_mode;
99
100         memset(&ht_cap, 0, sizeof(ht_cap));
101
102         if (!ht_cap_ie || !sband->ht_cap.ht_supported)
103                 goto apply;
104
105         ht_cap.ht_supported = true;
106
107         own_cap = sband->ht_cap;
108
109         /*
110          * If user has specified capability over-rides, take care
111          * of that if the station we're setting up is the AP that
112          * we advertised a restricted capability set to. Override
113          * our own capabilities and then use those below.
114          */
115         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
116             !test_sta_flag(sta, WLAN_STA_TDLS_PEER))
117                 ieee80211_apply_htcap_overrides(sdata, &own_cap);
118
119         /*
120          * The bits listed in this expression should be
121          * the same for the peer and us, if the station
122          * advertises more then we can't use those thus
123          * we mask them out.
124          */
125         ht_cap.cap = le16_to_cpu(ht_cap_ie->cap_info) &
126                 (own_cap.cap | ~(IEEE80211_HT_CAP_LDPC_CODING |
127                                  IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
128                                  IEEE80211_HT_CAP_GRN_FLD |
129                                  IEEE80211_HT_CAP_SGI_20 |
130                                  IEEE80211_HT_CAP_SGI_40 |
131                                  IEEE80211_HT_CAP_DSSSCCK40));
132
133         /*
134          * The STBC bits are asymmetric -- if we don't have
135          * TX then mask out the peer's RX and vice versa.
136          */
137         if (!(own_cap.cap & IEEE80211_HT_CAP_TX_STBC))
138                 ht_cap.cap &= ~IEEE80211_HT_CAP_RX_STBC;
139         if (!(own_cap.cap & IEEE80211_HT_CAP_RX_STBC))
140                 ht_cap.cap &= ~IEEE80211_HT_CAP_TX_STBC;
141
142         ampdu_info = ht_cap_ie->ampdu_params_info;
143         ht_cap.ampdu_factor =
144                 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
145         ht_cap.ampdu_density =
146                 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
147
148         /* own MCS TX capabilities */
149         tx_mcs_set_cap = own_cap.mcs.tx_params;
150
151         /* Copy peer MCS TX capabilities, the driver might need them. */
152         ht_cap.mcs.tx_params = ht_cap_ie->mcs.tx_params;
153
154         /* can we TX with MCS rates? */
155         if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
156                 goto apply;
157
158         /* Counting from 0, therefore +1 */
159         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
160                 max_tx_streams =
161                         ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
162                                 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
163         else
164                 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
165
166         /*
167          * 802.11n-2009 20.3.5 / 20.6 says:
168          * - indices 0 to 7 and 32 are single spatial stream
169          * - 8 to 31 are multiple spatial streams using equal modulation
170          *   [8..15 for two streams, 16..23 for three and 24..31 for four]
171          * - remainder are multiple spatial streams using unequal modulation
172          */
173         for (i = 0; i < max_tx_streams; i++)
174                 ht_cap.mcs.rx_mask[i] =
175                         own_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
176
177         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
178                 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
179                      i < IEEE80211_HT_MCS_MASK_LEN; i++)
180                         ht_cap.mcs.rx_mask[i] =
181                                 own_cap.mcs.rx_mask[i] &
182                                         ht_cap_ie->mcs.rx_mask[i];
183
184         /* handle MCS rate 32 too */
185         if (own_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
186                 ht_cap.mcs.rx_mask[32/8] |= 1;
187
188  apply:
189         changed = memcmp(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
190
191         memcpy(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
192
193         switch (sdata->vif.bss_conf.chandef.width) {
194         default:
195                 WARN_ON_ONCE(1);
196                 /* fall through */
197         case NL80211_CHAN_WIDTH_20_NOHT:
198         case NL80211_CHAN_WIDTH_20:
199                 bw = IEEE80211_STA_RX_BW_20;
200                 break;
201         case NL80211_CHAN_WIDTH_40:
202         case NL80211_CHAN_WIDTH_80:
203         case NL80211_CHAN_WIDTH_80P80:
204         case NL80211_CHAN_WIDTH_160:
205                 bw = ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
206                                 IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
207                 break;
208         }
209
210         if (bw != sta->sta.bandwidth)
211                 changed = true;
212         sta->sta.bandwidth = bw;
213
214         sta->cur_max_bandwidth =
215                 ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
216                                 IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
217
218         switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS)
219                         >> IEEE80211_HT_CAP_SM_PS_SHIFT) {
220         case WLAN_HT_CAP_SM_PS_INVALID:
221         case WLAN_HT_CAP_SM_PS_STATIC:
222                 smps_mode = IEEE80211_SMPS_STATIC;
223                 break;
224         case WLAN_HT_CAP_SM_PS_DYNAMIC:
225                 smps_mode = IEEE80211_SMPS_DYNAMIC;
226                 break;
227         case WLAN_HT_CAP_SM_PS_DISABLED:
228                 smps_mode = IEEE80211_SMPS_OFF;
229                 break;
230         }
231
232         if (smps_mode != sta->sta.smps_mode)
233                 changed = true;
234         sta->sta.smps_mode = smps_mode;
235
236         return changed;
237 }
238
239 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
240                                          enum ieee80211_agg_stop_reason reason)
241 {
242         int i;
243
244         cancel_work_sync(&sta->ampdu_mlme.work);
245
246         for (i = 0; i <  IEEE80211_NUM_TIDS; i++) {
247                 __ieee80211_stop_tx_ba_session(sta, i, reason);
248                 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
249                                                WLAN_REASON_QSTA_LEAVE_QBSS,
250                                                reason != AGG_STOP_DESTROY_STA &&
251                                                reason != AGG_STOP_PEER_REQUEST);
252         }
253 }
254
255 void ieee80211_ba_session_work(struct work_struct *work)
256 {
257         struct sta_info *sta =
258                 container_of(work, struct sta_info, ampdu_mlme.work);
259         struct tid_ampdu_tx *tid_tx;
260         int tid;
261
262         /*
263          * When this flag is set, new sessions should be
264          * blocked, and existing sessions will be torn
265          * down by the code that set the flag, so this
266          * need not run.
267          */
268         if (test_sta_flag(sta, WLAN_STA_BLOCK_BA))
269                 return;
270
271         mutex_lock(&sta->ampdu_mlme.mtx);
272         for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
273                 if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
274                         ___ieee80211_stop_rx_ba_session(
275                                 sta, tid, WLAN_BACK_RECIPIENT,
276                                 WLAN_REASON_QSTA_TIMEOUT, true);
277
278                 if (test_and_clear_bit(tid,
279                                        sta->ampdu_mlme.tid_rx_stop_requested))
280                         ___ieee80211_stop_rx_ba_session(
281                                 sta, tid, WLAN_BACK_RECIPIENT,
282                                 WLAN_REASON_UNSPECIFIED, true);
283
284                 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
285                 if (tid_tx) {
286                         /*
287                          * Assign it over to the normal tid_tx array
288                          * where it "goes live".
289                          */
290                         spin_lock_bh(&sta->lock);
291
292                         sta->ampdu_mlme.tid_start_tx[tid] = NULL;
293                         /* could there be a race? */
294                         if (sta->ampdu_mlme.tid_tx[tid])
295                                 kfree(tid_tx);
296                         else
297                                 ieee80211_assign_tid_tx(sta, tid, tid_tx);
298                         spin_unlock_bh(&sta->lock);
299
300                         ieee80211_tx_ba_session_handle_start(sta, tid);
301                         continue;
302                 }
303
304                 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
305                 if (tid_tx && test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
306                                                  &tid_tx->state))
307                         ___ieee80211_stop_tx_ba_session(sta, tid,
308                                                         AGG_STOP_LOCAL_REQUEST);
309         }
310         mutex_unlock(&sta->ampdu_mlme.mtx);
311 }
312
313 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
314                           const u8 *da, u16 tid,
315                           u16 initiator, u16 reason_code)
316 {
317         struct ieee80211_local *local = sdata->local;
318         struct sk_buff *skb;
319         struct ieee80211_mgmt *mgmt;
320         u16 params;
321
322         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
323         if (!skb)
324                 return;
325
326         skb_reserve(skb, local->hw.extra_tx_headroom);
327         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
328         memset(mgmt, 0, 24);
329         memcpy(mgmt->da, da, ETH_ALEN);
330         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
331         if (sdata->vif.type == NL80211_IFTYPE_AP ||
332             sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
333             sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
334                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
335         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
336                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
337         else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
338                 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
339
340         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
341                                           IEEE80211_STYPE_ACTION);
342
343         skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
344
345         mgmt->u.action.category = WLAN_CATEGORY_BACK;
346         mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
347         params = (u16)(initiator << 11);        /* bit 11 initiator */
348         params |= (u16)(tid << 12);             /* bit 15:12 TID number */
349
350         mgmt->u.action.u.delba.params = cpu_to_le16(params);
351         mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
352
353         ieee80211_tx_skb_tid(sdata, skb, tid);
354 }
355
356 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
357                              struct sta_info *sta,
358                              struct ieee80211_mgmt *mgmt, size_t len)
359 {
360         u16 tid, params;
361         u16 initiator;
362
363         params = le16_to_cpu(mgmt->u.action.u.delba.params);
364         tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
365         initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
366
367         ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n",
368                            mgmt->sa, initiator ? "initiator" : "recipient",
369                            tid,
370                            le16_to_cpu(mgmt->u.action.u.delba.reason_code));
371
372         if (initiator == WLAN_BACK_INITIATOR)
373                 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
374                                                true);
375         else
376                 __ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
377 }
378
379 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
380                                enum ieee80211_smps_mode smps, const u8 *da,
381                                const u8 *bssid)
382 {
383         struct ieee80211_local *local = sdata->local;
384         struct sk_buff *skb;
385         struct ieee80211_mgmt *action_frame;
386
387         /* 27 = header + category + action + smps mode */
388         skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
389         if (!skb)
390                 return -ENOMEM;
391
392         skb_reserve(skb, local->hw.extra_tx_headroom);
393         action_frame = (void *)skb_put(skb, 27);
394         memcpy(action_frame->da, da, ETH_ALEN);
395         memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
396         memcpy(action_frame->bssid, bssid, ETH_ALEN);
397         action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
398                                                   IEEE80211_STYPE_ACTION);
399         action_frame->u.action.category = WLAN_CATEGORY_HT;
400         action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
401         switch (smps) {
402         case IEEE80211_SMPS_AUTOMATIC:
403         case IEEE80211_SMPS_NUM_MODES:
404                 WARN_ON(1);
405         case IEEE80211_SMPS_OFF:
406                 action_frame->u.action.u.ht_smps.smps_control =
407                                 WLAN_HT_SMPS_CONTROL_DISABLED;
408                 break;
409         case IEEE80211_SMPS_STATIC:
410                 action_frame->u.action.u.ht_smps.smps_control =
411                                 WLAN_HT_SMPS_CONTROL_STATIC;
412                 break;
413         case IEEE80211_SMPS_DYNAMIC:
414                 action_frame->u.action.u.ht_smps.smps_control =
415                                 WLAN_HT_SMPS_CONTROL_DYNAMIC;
416                 break;
417         }
418
419         /* we'll do more on status of this frame */
420         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
421         ieee80211_tx_skb(sdata, skb);
422
423         return 0;
424 }
425
426 void ieee80211_request_smps_work(struct work_struct *work)
427 {
428         struct ieee80211_sub_if_data *sdata =
429                 container_of(work, struct ieee80211_sub_if_data,
430                              u.mgd.request_smps_work);
431
432         mutex_lock(&sdata->u.mgd.mtx);
433         __ieee80211_request_smps(sdata, sdata->u.mgd.driver_smps_mode);
434         mutex_unlock(&sdata->u.mgd.mtx);
435 }
436
437 void ieee80211_request_smps(struct ieee80211_vif *vif,
438                             enum ieee80211_smps_mode smps_mode)
439 {
440         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
441
442         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
443                 return;
444
445         if (WARN_ON(smps_mode == IEEE80211_SMPS_OFF))
446                 smps_mode = IEEE80211_SMPS_AUTOMATIC;
447
448         if (sdata->u.mgd.driver_smps_mode == smps_mode)
449                 return;
450
451         sdata->u.mgd.driver_smps_mode = smps_mode;
452
453         ieee80211_queue_work(&sdata->local->hw,
454                              &sdata->u.mgd.request_smps_work);
455 }
456 /* this might change ... don't want non-open drivers using it */
457 EXPORT_SYMBOL_GPL(ieee80211_request_smps);