cfg80211: Enable GO operation on additional channels

Allow GO operation on a channel marked with IEEE80211_CHAN_GO_CONCURRENT
iff there is an active station interface that is associated to
an AP operating on the same channel in the 2 GHz band or the same UNII band
(in the 5 GHz band). This relaxation is not allowed if the channel is
marked with IEEE80211_CHAN_RADAR.

Note that this is a permissive approach to the FCC definitions,
that require a clear assessment that the device operating the AP is
an authorized master, i.e., with radar detection and DFS capabilities.

It is assumed that such restrictions are enforced by user space.
Furthermore, it is assumed, that if the conditions that allowed for
the operation of the GO on such a channel change, i.e., the station
interface disconnected from the AP, it is the responsibility of user
space to evacuate the GO from the channel.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/net/wireless/reg.h b/net/wireless/reg.h
index 37c180df34b7..334a53af0fc8 100644
--- a/net/wireless/reg.h
+++ b/net/wireless/reg.h
@@ -104,4 +104,16 @@ void regulatory_hint_country_ie(struct wiphy *wiphy,
  */
 void regulatory_hint_disconnect(void);
 
+/**
+ * cfg80211_get_unii - get the U-NII band for the frequency
+ * @freq: the frequency for which we want to get the UNII band.
+
+ * Get a value specifying the U-NII band frequency belongs to.
+ * U-NII bands are defined by the FCC in C.F.R 47 part 15.
+ *
+ * Returns -EINVAL if freq is invalid, 0 for UNII-1, 1 for UNII-2A,
+ * 2 for UNII-2B, 3 for UNII-2C and 4 for UNII-3.
+ */
+int cfg80211_get_unii(int freq);
+
 #endif  /* __NET_WIRELESS_REG_H */