4 files changed, 106 insertions, 15 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 209cacee5285..05ba3539b77e 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -7,7 +7,7 @@
  * Copyright 2008 Michael Wu <flamingice@sourmilk.net>
  * Copyright 2008 Luis Carlos Cobo <luisca@cozybit.com>
  * Copyright 2008 Michael Buesch <mb@bu3sch.de>
- * Copyright 2008 Luis R. Rodriguez <lrodriguez@atheros.com>
+ * Copyright 2008, 2009 Luis R. Rodriguez <lrodriguez@atheros.com>
  * Copyright 2008 Jouni Malinen <jouni.malinen@atheros.com>
  * Copyright 2008 Colin McCabe <colin@cozybit.com>
  *
@@ -166,6 +166,22 @@
  *      set (%NL80211_ATTR_REG_TYPE), if the type of regulatory domain is
  *      %NL80211_REG_TYPE_COUNTRY the alpha2 to which we have moved on
  *      to (%NL80211_ATTR_REG_ALPHA2).
+ * @NL80211_CMD_REG_BEACON_HINT: indicates to userspace that an AP beacon
+ *      has been found while world roaming thus enabling active scan or
+ *      any mode of operation that initiates TX (beacons) on a channel
+ *      where we would not have been able to do either before. As an example
+ *      if you are world roaming (regulatory domain set to world or if your
+ *      driver is using a custom world roaming regulatory domain) and while
+ *      doing a passive scan on the 5 GHz band you find an AP there (if not
+ *      on a DFS channel) you will now be able to actively scan for that AP
+ *      or use AP mode on your card on that same channel. Note that this will
+ *      never be used for channels 1-11 on the 2 GHz band as they are always
+ *      enabled world wide. This beacon hint is only sent if your device had
+ *      either disabled active scanning or beaconing on a channel. We send to
+ *      userspace the wiphy on which we removed a restriction from
+ *      (%NL80211_ATTR_WIPHY) and the channel on which this occurred
+ *      before (%NL80211_ATTR_FREQ_BEFORE) and after (%NL80211_ATTR_FREQ_AFTER)
+ *      the beacon hint was processed.
  *
  * @NL80211_CMD_AUTHENTICATE: authentication request and notification.
  *      This command is used both as a command (request to authenticate) and
@@ -270,6 +286,8 @@ enum nl80211_commands {
 
         NL80211_CMD_MICHAEL_MIC_FAILURE,
 
+        NL80211_CMD_REG_BEACON_HINT,
+
         /* add new commands above here */
 
         /* used to define NL80211_CMD_MAX below */
@@ -288,6 +306,7 @@ enum nl80211_commands {
 #define NL80211_CMD_ASSOCIATE NL80211_CMD_ASSOCIATE
 #define NL80211_CMD_DEAUTHENTICATE NL80211_CMD_DEAUTHENTICATE
 #define NL80211_CMD_DISASSOCIATE NL80211_CMD_DISASSOCIATE
+#define NL80211_CMD_REG_BEACON_HINT NL80211_CMD_REG_BEACON_HINT
 
 /**
  * enum nl80211_attrs - nl80211 netlink attributes
@@ -423,6 +442,17 @@ enum nl80211_commands {
  * @NL80211_ATTR_KEY_TYPE: Key Type, see &enum nl80211_key_type, represented as
  *      a u32
  *
+ * @NL80211_ATTR_FREQ_BEFORE: A channel which has suffered a regulatory change
+ *      due to considerations from a beacon hint. This attribute reflects
+ *      the state of the channel _before_ the beacon hint processing. This
+ *      attributes consists of a nested attribute containing
+ *      NL80211_FREQUENCY_ATTR_*
+ * @NL80211_ATTR_FREQ_AFTER: A channel which has suffered a regulatory change
+ *      due to considerations from a beacon hint. This attribute reflects
+ *      the state of the channel _after_ the beacon hint processing. This
+ *      attributes consists of a nested attribute containing
+ *      NL80211_FREQUENCY_ATTR_*
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -511,6 +541,8 @@ enum nl80211_attrs {
 
         NL80211_ATTR_MAX_SCAN_IE_LEN,
 
+        NL80211_ATTR_FREQ_BEFORE,
+        NL80211_ATTR_FREQ_AFTER,
         /* add attributes here, update the policy in nl80211.c */
 
         __NL80211_ATTR_AFTER_LAST,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 7285bdc4e598..85b5aa3c76f8 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3491,6 +3491,60 @@ void nl80211_michael_mic_failure(struct cfg80211_registered_device *rdev,
         nlmsg_free(msg);
 }
 
+void nl80211_send_beacon_hint_event(struct wiphy *wiphy,
+                                    struct ieee80211_channel *channel_before,
+                                    struct ieee80211_channel *channel_after)
+{
+        struct sk_buff *msg;
+        void *hdr;
+        struct nlattr *nl_freq;
+
+        msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
+        if (!msg)
+                return;
+
+        hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_REG_BEACON_HINT);
+        if (!hdr) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        /*
+         * Since we are applying the beacon hint to a wiphy we know its
+         * wiphy_idx is valid
+         */
+        NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, get_wiphy_idx(wiphy));
+
+        /* Before */
+        nl_freq = nla_nest_start(msg, NL80211_ATTR_FREQ_BEFORE);
+        if (!nl_freq)
+                goto nla_put_failure;
+        if (nl80211_msg_put_channel(msg, channel_before))
+                goto nla_put_failure;
+        nla_nest_end(msg, nl_freq);
+
+        /* After */
+        nl_freq = nla_nest_start(msg, NL80211_ATTR_FREQ_AFTER);
+        if (!nl_freq)
+                goto nla_put_failure;
+        if (nl80211_msg_put_channel(msg, channel_after))
+                goto nla_put_failure;
+        nla_nest_end(msg, nl_freq);
+
+        if (genlmsg_end(msg, hdr) < 0) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        genlmsg_multicast(msg, 0, nl80211_regulatory_mcgrp.id, GFP_ATOMIC);
+
+        return;
+
+nla_put_failure:
+        genlmsg_cancel(msg, hdr);
+        nlmsg_free(msg);
+}
+
 /* initialisation/exit functions */
 
 int nl80211_init(void)
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index e4b92cccd157..b3aaa59afa08 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -29,4 +29,9 @@ nl80211_michael_mic_failure(struct cfg80211_registered_device *rdev,
                             enum nl80211_key_type key_type,
                             int key_id, const u8 *tsc);
 
+extern void
+nl80211_send_beacon_hint_event(struct wiphy *wiphy,
+                               struct ieee80211_channel *channel_before,
+                               struct ieee80211_channel *channel_after);
+
 #endif /* __NET_WIRELESS_NL80211_H */
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 4af4304cec3e..574e217bcc86 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -1049,18 +1049,10 @@ static void handle_reg_beacon(struct wiphy *wiphy,
                               unsigned int chan_idx,
                               struct reg_beacon *reg_beacon)
 {
-#ifdef CONFIG_CFG80211_REG_DEBUG
-#define REG_DEBUG_BEACON_FLAG(desc) \
-        printk(KERN_DEBUG "cfg80211: Enabling " desc " on " \
-                "frequency: %d MHz (Ch %d) on %s\n", \
-                reg_beacon->chan.center_freq, \
-                ieee80211_frequency_to_channel(reg_beacon->chan.center_freq), \
-                wiphy_name(wiphy));
-#else
-#define REG_DEBUG_BEACON_FLAG(desc) do {} while (0)
-#endif
         struct ieee80211_supported_band *sband;
         struct ieee80211_channel *chan;
+        bool channel_changed = false;
+        struct ieee80211_channel chan_before;
 
         assert_cfg80211_lock();
 
@@ -1070,20 +1062,28 @@ static void handle_reg_beacon(struct wiphy *wiphy,
         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
                 return;
 
+        if (chan->beacon_found)
+                return;
+
+        chan->beacon_found = true;
+
+        chan_before.center_freq = chan->center_freq;
+        chan_before.flags = chan->flags;
+
         if ((chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) &&
             !(chan->orig_flags & IEEE80211_CHAN_PASSIVE_SCAN)) {
                 chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
-                REG_DEBUG_BEACON_FLAG("active scanning");
+                channel_changed = true;
         }
 
         if ((chan->flags & IEEE80211_CHAN_NO_IBSS) &&
             !(chan->orig_flags & IEEE80211_CHAN_NO_IBSS)) {
                 chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
-                REG_DEBUG_BEACON_FLAG("beaconing");
+                channel_changed = true;
         }
 
-        chan->beacon_found = true;
-#undef REG_DEBUG_BEACON_FLAG
+        if (channel_changed)
+                nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
 }
 
 /*