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 <linux/export.h>
16 #include <net/mac80211.h>
17 #include "ieee80211_i.h"
18 #include "driver-trace.h"
21 * Tell our hardware to disable PS.
22 * Optionally inform AP that we will go to sleep so that it will buffer
23 * the frames while we are doing off-channel work. This is optional
24 * because we *may* be doing work on-operating channel, and want our
25 * hardware unconditionally awake, but still let the AP send us normal frames.
27 static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata,
30 struct ieee80211_local *local = sdata->local;
31 struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
33 local->offchannel_ps_enabled = false;
35 /* FIXME: what to do when local->pspolling is true? */
37 del_timer_sync(&local->dynamic_ps_timer);
38 del_timer_sync(&ifmgd->bcn_mon_timer);
39 del_timer_sync(&ifmgd->conn_mon_timer);
41 cancel_work_sync(&local->dynamic_ps_enable_work);
43 if (local->hw.conf.flags & IEEE80211_CONF_PS) {
44 local->offchannel_ps_enabled = true;
45 local->hw.conf.flags &= ~IEEE80211_CONF_PS;
46 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
49 if (tell_ap && (!local->offchannel_ps_enabled ||
50 !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)))
52 * If power save was enabled, no need to send a nullfunc
53 * frame because AP knows that we are sleeping. But if the
54 * hardware is creating the nullfunc frame for power save
55 * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
56 * enabled) and power save was enabled, the firmware just
57 * sent a null frame with power save disabled. So we need
58 * to send a new nullfunc frame to inform the AP that we
61 ieee80211_send_nullfunc(local, sdata, 1);
64 /* inform AP that we are awake again, unless power save is enabled */
65 static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
67 struct ieee80211_local *local = sdata->local;
70 ieee80211_send_nullfunc(local, sdata, 0);
71 else if (local->offchannel_ps_enabled) {
73 * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware
74 * will send a nullfunc frame with the powersave bit set
75 * even though the AP already knows that we are sleeping.
76 * This could be avoided by sending a null frame with power
77 * save bit disabled before enabling the power save, but
78 * this doesn't gain anything.
80 * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need
81 * to send a nullfunc frame because AP already knows that
82 * we are sleeping, let's just enable power save mode in
85 /* TODO: Only set hardware if CONF_PS changed?
86 * TODO: Should we set offchannel_ps_enabled to false?
88 local->hw.conf.flags |= IEEE80211_CONF_PS;
89 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
90 } else if (local->hw.conf.dynamic_ps_timeout > 0) {
92 * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer
93 * had been running before leaving the operating channel,
94 * restart the timer now and send a nullfunc frame to inform
95 * the AP that we are awake.
97 ieee80211_send_nullfunc(local, sdata, 0);
98 mod_timer(&local->dynamic_ps_timer, jiffies +
99 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
102 ieee80211_sta_reset_beacon_monitor(sdata);
103 ieee80211_sta_reset_conn_monitor(sdata);
106 void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
107 bool offchannel_ps_enable)
109 struct ieee80211_sub_if_data *sdata;
112 * notify the AP about us leaving the channel and stop all
115 mutex_lock(&local->iflist_mtx);
116 list_for_each_entry(sdata, &local->interfaces, list) {
117 if (!ieee80211_sdata_running(sdata))
120 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
121 set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
123 /* Check to see if we should disable beaconing. */
124 if (sdata->vif.type == NL80211_IFTYPE_AP ||
125 sdata->vif.type == NL80211_IFTYPE_ADHOC ||
126 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
127 ieee80211_bss_info_change_notify(
128 sdata, BSS_CHANGED_BEACON_ENABLED);
130 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
131 netif_tx_stop_all_queues(sdata->dev);
132 if (offchannel_ps_enable &&
133 (sdata->vif.type == NL80211_IFTYPE_STATION) &&
134 sdata->u.mgd.associated)
135 ieee80211_offchannel_ps_enable(sdata, true);
138 mutex_unlock(&local->iflist_mtx);
141 void ieee80211_offchannel_enable_all_ps(struct ieee80211_local *local,
144 struct ieee80211_sub_if_data *sdata;
146 mutex_lock(&local->iflist_mtx);
147 list_for_each_entry(sdata, &local->interfaces, list) {
148 if (!ieee80211_sdata_running(sdata))
151 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
152 sdata->u.mgd.associated)
153 ieee80211_offchannel_ps_enable(sdata, tell_ap);
155 mutex_unlock(&local->iflist_mtx);
158 void ieee80211_offchannel_return(struct ieee80211_local *local,
159 bool offchannel_ps_disable)
161 struct ieee80211_sub_if_data *sdata;
163 mutex_lock(&local->iflist_mtx);
164 list_for_each_entry(sdata, &local->interfaces, list) {
165 if (!ieee80211_sdata_running(sdata))
168 /* Tell AP we're back */
169 if (offchannel_ps_disable &&
170 sdata->vif.type == NL80211_IFTYPE_STATION) {
171 if (sdata->u.mgd.associated)
172 ieee80211_offchannel_ps_disable(sdata);
175 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
176 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
178 * This may wake up queues even though the driver
179 * currently has them stopped. This is not very
180 * likely, since the driver won't have gotten any
181 * (or hardly any) new packets while we weren't
182 * on the right channel, and even if it happens
183 * it will at most lead to queueing up one more
184 * packet per queue in mac80211 rather than on
185 * the interface qdisc.
187 netif_tx_wake_all_queues(sdata->dev);
190 if (sdata->vif.type == NL80211_IFTYPE_AP ||
191 sdata->vif.type == NL80211_IFTYPE_ADHOC ||
192 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
193 ieee80211_bss_info_change_notify(
194 sdata, BSS_CHANGED_BEACON_ENABLED);
196 mutex_unlock(&local->iflist_mtx);
199 static void ieee80211_hw_roc_start(struct work_struct *work)
201 struct ieee80211_local *local =
202 container_of(work, struct ieee80211_local, hw_roc_start);
203 struct ieee80211_sub_if_data *sdata;
205 mutex_lock(&local->mtx);
207 if (!local->hw_roc_channel) {
208 mutex_unlock(&local->mtx);
212 if (local->hw_roc_skb) {
213 sdata = IEEE80211_DEV_TO_SUB_IF(local->hw_roc_dev);
214 ieee80211_tx_skb(sdata, local->hw_roc_skb);
215 local->hw_roc_skb = NULL;
217 cfg80211_ready_on_channel(local->hw_roc_dev,
218 local->hw_roc_cookie,
219 local->hw_roc_channel,
220 local->hw_roc_channel_type,
221 local->hw_roc_duration,
225 ieee80211_recalc_idle(local);
227 mutex_unlock(&local->mtx);
230 void ieee80211_ready_on_channel(struct ieee80211_hw *hw)
232 struct ieee80211_local *local = hw_to_local(hw);
234 trace_api_ready_on_channel(local);
236 ieee80211_queue_work(hw, &local->hw_roc_start);
238 EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel);
240 static void ieee80211_hw_roc_done(struct work_struct *work)
242 struct ieee80211_local *local =
243 container_of(work, struct ieee80211_local, hw_roc_done);
245 mutex_lock(&local->mtx);
247 if (!local->hw_roc_channel) {
248 mutex_unlock(&local->mtx);
252 if (!local->hw_roc_for_tx)
253 cfg80211_remain_on_channel_expired(local->hw_roc_dev,
254 local->hw_roc_cookie,
255 local->hw_roc_channel,
256 local->hw_roc_channel_type,
259 local->hw_roc_channel = NULL;
260 local->hw_roc_cookie = 0;
262 ieee80211_recalc_idle(local);
264 mutex_unlock(&local->mtx);
267 void ieee80211_remain_on_channel_expired(struct ieee80211_hw *hw)
269 struct ieee80211_local *local = hw_to_local(hw);
271 trace_api_remain_on_channel_expired(local);
273 ieee80211_queue_work(hw, &local->hw_roc_done);
275 EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired);
277 void ieee80211_hw_roc_setup(struct ieee80211_local *local)
279 INIT_WORK(&local->hw_roc_start, ieee80211_hw_roc_start);
280 INIT_WORK(&local->hw_roc_done, ieee80211_hw_roc_done);