2 * Off-channel operation helpers
4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
5 * Copyright 2004, Instant802 Networks, Inc.
6 * Copyright 2005, Devicescape Software, Inc.
7 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9 * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
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.
15 #include <net/mac80211.h>
16 #include "ieee80211_i.h"
17 #include "driver-trace.h"
20 * inform AP that we will go to sleep so that it will buffer the frames
23 static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
25 struct ieee80211_local *local = sdata->local;
26 struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
28 local->offchannel_ps_enabled = false;
30 /* FIXME: what to do when local->pspolling is true? */
32 del_timer_sync(&local->dynamic_ps_timer);
33 del_timer_sync(&ifmgd->bcn_mon_timer);
34 del_timer_sync(&ifmgd->conn_mon_timer);
36 cancel_work_sync(&local->dynamic_ps_enable_work);
38 if (local->hw.conf.flags & IEEE80211_CONF_PS) {
39 local->offchannel_ps_enabled = true;
40 local->hw.conf.flags &= ~IEEE80211_CONF_PS;
41 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
44 if (!(local->offchannel_ps_enabled) ||
45 !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK))
47 * If power save was enabled, no need to send a nullfunc
48 * frame because AP knows that we are sleeping. But if the
49 * hardware is creating the nullfunc frame for power save
50 * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
51 * enabled) and power save was enabled, the firmware just
52 * sent a null frame with power save disabled. So we need
53 * to send a new nullfunc frame to inform the AP that we
56 ieee80211_send_nullfunc(local, sdata, 1);
59 /* inform AP that we are awake again, unless power save is enabled */
60 static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
62 struct ieee80211_local *local = sdata->local;
65 ieee80211_send_nullfunc(local, sdata, 0);
66 else if (local->offchannel_ps_enabled) {
68 * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware
69 * will send a nullfunc frame with the powersave bit set
70 * even though the AP already knows that we are sleeping.
71 * This could be avoided by sending a null frame with power
72 * save bit disabled before enabling the power save, but
73 * this doesn't gain anything.
75 * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need
76 * to send a nullfunc frame because AP already knows that
77 * we are sleeping, let's just enable power save mode in
80 local->hw.conf.flags |= IEEE80211_CONF_PS;
81 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
82 } else if (local->hw.conf.dynamic_ps_timeout > 0) {
84 * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer
85 * had been running before leaving the operating channel,
86 * restart the timer now and send a nullfunc frame to inform
87 * the AP that we are awake.
89 ieee80211_send_nullfunc(local, sdata, 0);
90 mod_timer(&local->dynamic_ps_timer, jiffies +
91 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
94 ieee80211_sta_reset_beacon_monitor(sdata);
95 ieee80211_sta_reset_conn_monitor(sdata);
98 void ieee80211_offchannel_stop_beaconing(struct ieee80211_local *local)
100 struct ieee80211_sub_if_data *sdata;
102 mutex_lock(&local->iflist_mtx);
103 list_for_each_entry(sdata, &local->interfaces, list) {
104 if (!ieee80211_sdata_running(sdata))
107 /* disable beaconing */
108 if (sdata->vif.type == NL80211_IFTYPE_AP ||
109 sdata->vif.type == NL80211_IFTYPE_ADHOC ||
110 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
111 ieee80211_bss_info_change_notify(
112 sdata, BSS_CHANGED_BEACON_ENABLED);
115 * only handle non-STA interfaces here, STA interfaces
116 * are handled in ieee80211_offchannel_stop_station(),
117 * e.g., from the background scan state machine.
119 * In addition, do not stop monitor interface to allow it to be
120 * used from user space controlled off-channel operations.
122 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
123 sdata->vif.type != NL80211_IFTYPE_MONITOR) {
124 set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
125 netif_tx_stop_all_queues(sdata->dev);
128 mutex_unlock(&local->iflist_mtx);
131 void ieee80211_offchannel_stop_station(struct ieee80211_local *local)
133 struct ieee80211_sub_if_data *sdata;
136 * notify the AP about us leaving the channel and stop all STA interfaces
138 mutex_lock(&local->iflist_mtx);
139 list_for_each_entry(sdata, &local->interfaces, list) {
140 if (!ieee80211_sdata_running(sdata))
143 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
144 set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
145 netif_tx_stop_all_queues(sdata->dev);
146 if (sdata->u.mgd.associated)
147 ieee80211_offchannel_ps_enable(sdata);
150 mutex_unlock(&local->iflist_mtx);
153 void ieee80211_offchannel_return(struct ieee80211_local *local,
154 bool enable_beaconing)
156 struct ieee80211_sub_if_data *sdata;
158 mutex_lock(&local->iflist_mtx);
159 list_for_each_entry(sdata, &local->interfaces, list) {
160 if (!ieee80211_sdata_running(sdata))
163 /* Tell AP we're back */
164 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
165 if (sdata->u.mgd.associated)
166 ieee80211_offchannel_ps_disable(sdata);
169 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
170 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
172 * This may wake up queues even though the driver
173 * currently has them stopped. This is not very
174 * likely, since the driver won't have gotten any
175 * (or hardly any) new packets while we weren't
176 * on the right channel, and even if it happens
177 * it will at most lead to queueing up one more
178 * packet per queue in mac80211 rather than on
179 * the interface qdisc.
181 netif_tx_wake_all_queues(sdata->dev);
184 /* re-enable beaconing */
185 if (enable_beaconing &&
186 (sdata->vif.type == NL80211_IFTYPE_AP ||
187 sdata->vif.type == NL80211_IFTYPE_ADHOC ||
188 sdata->vif.type == NL80211_IFTYPE_MESH_POINT))
189 ieee80211_bss_info_change_notify(
190 sdata, BSS_CHANGED_BEACON_ENABLED);
192 mutex_unlock(&local->iflist_mtx);
195 static void ieee80211_hw_roc_start(struct work_struct *work)
197 struct ieee80211_local *local =
198 container_of(work, struct ieee80211_local, hw_roc_start);
200 mutex_lock(&local->mtx);
202 if (!local->hw_roc_channel) {
203 mutex_unlock(&local->mtx);
207 ieee80211_recalc_idle(local);
209 cfg80211_ready_on_channel(local->hw_roc_dev, local->hw_roc_cookie,
210 local->hw_roc_channel,
211 local->hw_roc_channel_type,
212 local->hw_roc_duration,
214 mutex_unlock(&local->mtx);
217 void ieee80211_ready_on_channel(struct ieee80211_hw *hw)
219 struct ieee80211_local *local = hw_to_local(hw);
221 trace_api_ready_on_channel(local);
223 ieee80211_queue_work(hw, &local->hw_roc_start);
225 EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel);
227 static void ieee80211_hw_roc_done(struct work_struct *work)
229 struct ieee80211_local *local =
230 container_of(work, struct ieee80211_local, hw_roc_done);
232 mutex_lock(&local->mtx);
234 if (!local->hw_roc_channel) {
235 mutex_unlock(&local->mtx);
239 cfg80211_remain_on_channel_expired(local->hw_roc_dev,
240 local->hw_roc_cookie,
241 local->hw_roc_channel,
242 local->hw_roc_channel_type,
245 local->hw_roc_channel = NULL;
246 local->hw_roc_cookie = 0;
248 ieee80211_recalc_idle(local);
250 mutex_unlock(&local->mtx);
253 void ieee80211_remain_on_channel_expired(struct ieee80211_hw *hw)
255 struct ieee80211_local *local = hw_to_local(hw);
257 trace_api_remain_on_channel_expired(local);
259 ieee80211_queue_work(hw, &local->hw_roc_done);
261 EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired);
263 void ieee80211_hw_roc_setup(struct ieee80211_local *local)
265 INIT_WORK(&local->hw_roc_start, ieee80211_hw_roc_start);
266 INIT_WORK(&local->hw_roc_done, ieee80211_hw_roc_done);