aboutsummaryrefslogtreecommitdiff
path: root/net/mac80211/ht.c
blob: 1b503f3cc54cdee70372403e252ebd63cb7885c2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
/*
 * HT handling
 *
 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
 * Copyright 2002-2005, Instant802 Networks, Inc.
 * Copyright 2005-2006, Devicescape Software, Inc.
 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
 * Copyright 2007-2008, Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/ieee80211.h>
#include <net/wireless.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"

void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
				       struct ieee80211_ht_cap *ht_cap_ie,
				       struct ieee80211_sta_ht_cap *ht_cap)
{
	u8 ampdu_info, tx_mcs_set_cap;
	int i, max_tx_streams;

	BUG_ON(!ht_cap);

	memset(ht_cap, 0, sizeof(*ht_cap));

	if (!ht_cap_ie)
		return;

	ht_cap->ht_supported = true;

	ht_cap->cap = le16_to_cpu(ht_cap_ie->cap_info) & sband->ht_cap.cap;
	ht_cap->cap &= ~IEEE80211_HT_CAP_SM_PS;
	ht_cap->cap |= sband->ht_cap.cap & IEEE80211_HT_CAP_SM_PS;

	ampdu_info = ht_cap_ie->ampdu_params_info;
	ht_cap->ampdu_factor =
		ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
	ht_cap->ampdu_density =
		(ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;

	/* own MCS TX capabilities */
	tx_mcs_set_cap = sband->ht_cap.mcs.tx_params;

	/* can we TX with MCS rates? */
	if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
		return;

	/* Counting from 0, therefore +1 */
	if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
		max_tx_streams =
			((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
				>> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
	else
		max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;

	/*
	 * 802.11n D5.0 20.3.5 / 20.6 says:
	 * - indices 0 to 7 and 32 are single spatial stream
	 * - 8 to 31 are multiple spatial streams using equal modulation
	 *   [8..15 for two streams, 16..23 for three and 24..31 for four]
	 * - remainder are multiple spatial streams using unequal modulation
	 */
	for (i = 0; i < max_tx_streams; i++)
		ht_cap->mcs.rx_mask[i] =
			sband->ht_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];

	if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
		for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
		     i < IEEE80211_HT_MCS_MASK_LEN; i++)
			ht_cap->mcs.rx_mask[i] =
				sband->ht_cap.mcs.rx_mask[i] &
					ht_cap_ie->mcs.rx_mask[i];

	/* handle MCS rate 32 too */
	if (sband->ht_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
		ht_cap->mcs.rx_mask[32/8] |= 1;
}

/*
 * ieee80211_enable_ht should be called only after the operating band
 * has been determined as ht configuration depends on the hw's
 * HT abilities for a specific band.
 */
u32 ieee80211_enable_ht(struct ieee80211_sub_if_data *sdata,
			struct ieee80211_ht_info *hti,
			u16 ap_ht_cap_flags)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_supported_band *sband;
	struct ieee80211_bss_ht_conf ht;
	u32 changed = 0;
	bool enable_ht = true, ht_changed;
	enum nl80211_channel_type channel_type = NL80211_CHAN_NO_HT;

	sband = local->hw.wiphy->bands[local->hw.conf.channel->band];

	memset(&ht, 0, sizeof(ht));

	/* HT is not supported */
	if (!sband->ht_cap.ht_supported)
		enable_ht = false;

	/* check that channel matches the right operating channel */
	if (local->hw.conf.channel->center_freq !=
	    ieee80211_channel_to_frequency(hti->control_chan))
		enable_ht = false;

	if (enable_ht) {
		channel_type = NL80211_CHAN_HT20;

		if (!(ap_ht_cap_flags & IEEE80211_HT_CAP_40MHZ_INTOLERANT) &&
		    (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) &&
		    (hti->ht_param & IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
			switch(hti->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
			case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
				channel_type = NL80211_CHAN_HT40PLUS;
				break;
			case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
				channel_type = NL80211_CHAN_HT40MINUS;
				break;
			}
		}
	}

	ht_changed = conf_is_ht(&local->hw.conf) != enable_ht ||
		     channel_type != local->hw.conf.channel_type;

	local->oper_channel_type = channel_type;

	if (ht_changed) {
                /* channel_type change automatically detected */
		ieee80211_hw_config(local, 0);
        }

	/* disable HT */
	if (!enable_ht)
		return 0;

	ht.operation_mode = le16_to_cpu(hti->operation_mode);

	/* if bss configuration changed store the new one */
	if (memcmp(&sdata->vif.bss_conf.ht, &ht, sizeof(ht))) {
		changed |= BSS_CHANGED_HT;
		sdata->vif.bss_conf.ht = ht;
	}

	return changed;
}

void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta)
{
	struct ieee80211_local *local = sta->local;
	int i;

	for (i = 0; i <  STA_TID_NUM; i++) {
		ieee80211_stop_tx_ba_session(&local->hw, sta->sta.addr, i,
					     WLAN_BACK_INITIATOR);
		ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr, i,
						 WLAN_BACK_RECIPIENT,
						 WLAN_REASON_QSTA_LEAVE_QBSS);
	}
}

void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
			  const u8 *da, u16 tid,
			  u16 initiator, u16 reason_code)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_sta *ifsta = &sdata->u.sta;
	struct sk_buff *skb;
	struct ieee80211_mgmt *mgmt;
	u16 params;

	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);

	if (!skb) {
		printk(KERN_ERR "%s: failed to allocate buffer "
					"for delba frame\n", sdata->dev->name);
		return;
	}

	skb_reserve(skb, local->hw.extra_tx_headroom);
	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
	memset(mgmt, 0, 24);
	memcpy(mgmt->da, da, ETH_ALEN);
	memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
	if (sdata->vif.type == NL80211_IFTYPE_AP ||
	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
		memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
	else
		memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
					  IEEE80211_STYPE_ACTION);

	skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));

	mgmt->u.action.category = WLAN_CATEGORY_BACK;
	mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
	params = (u16)(initiator << 11); 	/* bit 11 initiator */
	params |= (u16)(tid << 12); 		/* bit 15:12 TID number */

	mgmt->u.action.u.delba.params = cpu_to_le16(params);
	mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);

	ieee80211_tx_skb(sdata, skb, 1);
}

void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
			     struct sta_info *sta,
			     struct ieee80211_mgmt *mgmt, size_t len)
{
	struct ieee80211_local *local = sdata->local;
	u16 tid, params;
	u16 initiator;

	params = le16_to_cpu(mgmt->u.action.u.delba.params);
	tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
	initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;

#ifdef CONFIG_MAC80211_HT_DEBUG
	if (net_ratelimit())
		printk(KERN_DEBUG "delba from %pM (%s) tid %d reason code %d\n",
			mgmt->sa, initiator ? "initiator" : "recipient", tid,
			mgmt->u.action.u.delba.reason_code);
#endif /* CONFIG_MAC80211_HT_DEBUG */

	if (initiator == WLAN_BACK_INITIATOR)
		ieee80211_sta_stop_rx_ba_session(sdata, sta->sta.addr, tid,
						 WLAN_BACK_INITIATOR, 0);
	else { /* WLAN_BACK_RECIPIENT */
		spin_lock_bh(&sta->lock);
		sta->ampdu_mlme.tid_state_tx[tid] =
				HT_AGG_STATE_OPERATIONAL;
		spin_unlock_bh(&sta->lock);
		ieee80211_stop_tx_ba_session(&local->hw, sta->sta.addr, tid,
					     WLAN_BACK_RECIPIENT);
	}
}