blob: c36b1911987afec08262139ccaaf5e7887a17735 [file] [log] [blame]
Jouni Malinenb203ffc2009-12-23 13:15:40 +01001/*
2 * Off-channel operation helpers
3 *
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>
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#include <net/mac80211.h>
16#include "ieee80211_i.h"
17
18/*
19 * inform AP that we will go to sleep so that it will buffer the frames
20 * while we scan
21 */
22static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
23{
24 struct ieee80211_local *local = sdata->local;
25
26 local->offchannel_ps_enabled = false;
27
28 /* FIXME: what to do when local->pspolling is true? */
29
30 del_timer_sync(&local->dynamic_ps_timer);
31 cancel_work_sync(&local->dynamic_ps_enable_work);
32
33 if (local->hw.conf.flags & IEEE80211_CONF_PS) {
34 local->offchannel_ps_enabled = true;
35 local->hw.conf.flags &= ~IEEE80211_CONF_PS;
36 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
37 }
38
39 if (!(local->offchannel_ps_enabled) ||
40 !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK))
41 /*
42 * If power save was enabled, no need to send a nullfunc
43 * frame because AP knows that we are sleeping. But if the
44 * hardware is creating the nullfunc frame for power save
45 * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
46 * enabled) and power save was enabled, the firmware just
47 * sent a null frame with power save disabled. So we need
48 * to send a new nullfunc frame to inform the AP that we
49 * are again sleeping.
50 */
51 ieee80211_send_nullfunc(local, sdata, 1);
52}
53
54/* inform AP that we are awake again, unless power save is enabled */
55static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
56{
57 struct ieee80211_local *local = sdata->local;
58
59 if (!local->ps_sdata)
60 ieee80211_send_nullfunc(local, sdata, 0);
61 else if (local->offchannel_ps_enabled) {
62 /*
63 * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware
64 * will send a nullfunc frame with the powersave bit set
65 * even though the AP already knows that we are sleeping.
66 * This could be avoided by sending a null frame with power
67 * save bit disabled before enabling the power save, but
68 * this doesn't gain anything.
69 *
70 * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need
71 * to send a nullfunc frame because AP already knows that
72 * we are sleeping, let's just enable power save mode in
73 * hardware.
74 */
75 local->hw.conf.flags |= IEEE80211_CONF_PS;
76 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
77 } else if (local->hw.conf.dynamic_ps_timeout > 0) {
78 /*
79 * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer
80 * had been running before leaving the operating channel,
81 * restart the timer now and send a nullfunc frame to inform
82 * the AP that we are awake.
83 */
84 ieee80211_send_nullfunc(local, sdata, 0);
85 mod_timer(&local->dynamic_ps_timer, jiffies +
86 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
87 }
88}
89
90void ieee80211_offchannel_stop_beaconing(struct ieee80211_local *local)
91{
92 struct ieee80211_sub_if_data *sdata;
93
94 mutex_lock(&local->iflist_mtx);
95 list_for_each_entry(sdata, &local->interfaces, list) {
96 if (!ieee80211_sdata_running(sdata))
97 continue;
98
99 /* disable beaconing */
100 if (sdata->vif.type == NL80211_IFTYPE_AP ||
101 sdata->vif.type == NL80211_IFTYPE_ADHOC ||
102 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
103 ieee80211_bss_info_change_notify(
104 sdata, BSS_CHANGED_BEACON_ENABLED);
105
106 /*
107 * only handle non-STA interfaces here, STA interfaces
108 * are handled in ieee80211_offchannel_stop_station(),
Johannes Bergb8bc4b02009-12-23 13:15:42 +0100109 * e.g., from the background scan state machine.
110 *
111 * In addition, do not stop monitor interface to allow it to be
112 * used from user space controlled off-channel operations.
Jouni Malinenb203ffc2009-12-23 13:15:40 +0100113 */
Johannes Bergb8bc4b02009-12-23 13:15:42 +0100114 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
115 sdata->vif.type != NL80211_IFTYPE_MONITOR)
John W. Linvillecfa6cb22010-01-06 17:22:54 -0500116 netif_tx_stop_all_queues(sdata->dev);
Jouni Malinenb203ffc2009-12-23 13:15:40 +0100117 }
118 mutex_unlock(&local->iflist_mtx);
119}
120
121void ieee80211_offchannel_stop_station(struct ieee80211_local *local)
122{
123 struct ieee80211_sub_if_data *sdata;
124
125 /*
126 * notify the AP about us leaving the channel and stop all STA interfaces
127 */
128 mutex_lock(&local->iflist_mtx);
129 list_for_each_entry(sdata, &local->interfaces, list) {
130 if (!ieee80211_sdata_running(sdata))
131 continue;
132
133 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
John W. Linvillecfa6cb22010-01-06 17:22:54 -0500134 netif_tx_stop_all_queues(sdata->dev);
Jouni Malinenb203ffc2009-12-23 13:15:40 +0100135 if (sdata->u.mgd.associated)
136 ieee80211_offchannel_ps_enable(sdata);
137 }
138 }
139 mutex_unlock(&local->iflist_mtx);
140}
141
142void ieee80211_offchannel_return(struct ieee80211_local *local,
143 bool enable_beaconing)
144{
145 struct ieee80211_sub_if_data *sdata;
146
147 mutex_lock(&local->iflist_mtx);
148 list_for_each_entry(sdata, &local->interfaces, list) {
149 if (!ieee80211_sdata_running(sdata))
150 continue;
151
152 /* Tell AP we're back */
153 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
154 if (sdata->u.mgd.associated)
155 ieee80211_offchannel_ps_disable(sdata);
Jouni Malinenb203ffc2009-12-23 13:15:40 +0100156 }
157
Benoit Papillault93895752010-01-14 23:20:31 +0100158 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
159 netif_tx_wake_all_queues(sdata->dev);
160
Jouni Malinenb203ffc2009-12-23 13:15:40 +0100161 /* re-enable beaconing */
162 if (enable_beaconing &&
163 (sdata->vif.type == NL80211_IFTYPE_AP ||
164 sdata->vif.type == NL80211_IFTYPE_ADHOC ||
165 sdata->vif.type == NL80211_IFTYPE_MESH_POINT))
166 ieee80211_bss_info_change_notify(
167 sdata, BSS_CHANGED_BEACON_ENABLED);
168 }
169 mutex_unlock(&local->iflist_mtx);
170}