mac80211: process the CSA frame for mesh accordingly

Process the CSA frame according to the procedures define in IEEE Std
802.11-2012 section 10.9.8.4.3 as follow:
* The mesh channel switch parameters element (MCSP) must be availabe.
* If the MCSP's TTL is 1, drop the frame but still process the CSA.
* If the MCSP's precedence value is less than or equal to the current
  precedence value, drop the frame and do not process the CSA.
* The CSA frame is forwarded after TTL is decremented by 1 and the
  initiator field is set to 0. Transmit restrict field and others
  are maintained as is.
* No beacon or probe response frame are handled here.

Also, introduce the debug message used for mesh CSA purpose.

Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/net/mac80211/debug.h b/net/mac80211/debug.h
index 4ccc5ed6237d..493d68061f0c 100644
--- a/net/mac80211/debug.h
+++ b/net/mac80211/debug.h
@@ -44,6 +44,12 @@
 #define MAC80211_MESH_SYNC_DEBUG 0
 #endif
 
+#ifdef CONFIG_MAC80211_MESH_CSA_DEBUG
+#define MAC80211_MESH_CSA_DEBUG 1
+#else
+#define MAC80211_MESH_CSA_DEBUG 0
+#endif
+
 #ifdef CONFIG_MAC80211_MESH_PS_DEBUG
 #define MAC80211_MESH_PS_DEBUG 1
 #else
@@ -157,6 +163,10 @@ do {									\
         _sdata_dbg(MAC80211_MESH_SYNC_DEBUG,                            \
                    sdata, fmt, ##__VA_ARGS__)
 
+#define mcsa_dbg(sdata, fmt, ...)                                       \
+        _sdata_dbg(MAC80211_MESH_CSA_DEBUG,                             \
+                   sdata, fmt, ##__VA_ARGS__)
+
 #define mps_dbg(sdata, fmt, ...)                                        \
         _sdata_dbg(MAC80211_MESH_PS_DEBUG,                              \
                    sdata, fmt, ##__VA_ARGS__)