Currently the only way for wireless drivers to tell whether or not OFDM
is allowed on the current channel is to check the regulatory
information. However, this requires hodling cfg80211_mutex, which is not
visible to the drivers.

Other regulatory restrictions are provided as flags in the channel
definition, so let's do similarly with OFDM. This patch adds a new flag,
IEEE80211_CHAN_NO_OFDM, to tell drivers that OFDM on a channel is not
allowed. This flag is set on any channels for which regulatory indicates
that OFDM is prohibited.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
---
 include/net/cfg80211.h |    2 ++
 net/wireless/reg.c     |    2 ++
 2 files changed, 4 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 493fa0c..3d254e1 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -96,6 +96,7 @@ enum ieee80211_band {
  * 	is not permitted.
  * @IEEE80211_CHAN_NO_HT40MINUS: extension channel below this channel
  * 	is not permitted.
+ * @IEEE80211_CHAN_NO_OFDM: OFDM is not allowed on this channel.
  */
 enum ieee80211_channel_flags {
 	IEEE80211_CHAN_DISABLED		= 1<<0,
@@ -104,6 +105,7 @@ enum ieee80211_channel_flags {
 	IEEE80211_CHAN_RADAR		= 1<<3,
 	IEEE80211_CHAN_NO_HT40PLUS	= 1<<4,
 	IEEE80211_CHAN_NO_HT40MINUS	= 1<<5,
+	IEEE80211_CHAN_NO_OFDM		= 1<<6,
 };
 
 #define IEEE80211_CHAN_NO_HT40 \
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 2303ee7..0f3a8a1 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -680,6 +680,8 @@ static u32 map_regdom_flags(u32 rd_flags)
 		channel_flags |= IEEE80211_CHAN_NO_IBSS;
 	if (rd_flags & NL80211_RRF_DFS)
 		channel_flags |= IEEE80211_CHAN_RADAR;
+	if (rd_flags & NL80211_RRF_NO_OFDM)
+		channel_flags |= IEEE80211_CHAN_NO_OFDM;
 	return channel_flags;
 }
 
-- 
1.7.9.5