Flesh out the radar detection related operations for the ath driver.

This is in no way a complete DFS/radar detection implementation!
It merely creates an abstracted interface which allows for future
development of the DFS radar detection code.

Note: Net80211 already handles the bulk of the DFS machinery,
all we need to do here is figure out that a radar event has occured
and inform it as such. It then drives the DFS state engine for us.

The "null" DFS radar detection module is included by default;
it doesn't require a device line.

This commit:

* Adds a simple abstracted layer for radar detection state -
  sys/dev/ath/ath_dfs/;
* Implements a null DFS module which doesn't do anything;
  (ie, implements the exact behaviour at the moment);
* Adds hooks to the ath driver to process received radar events
  and gives the DFS module a chance to determine whether
  a radar has been detected.

Obtained from:	Atheros

1 files changed, 4 insertions, 0 deletions

diff --git a/sys/modules/ath/Makefile b/sys/modules/ath/Makefile
index 6b093a9..49f7fa6 100644
--- a/sys/modules/ath/Makefile
+++ b/sys/modules/ath/Makefile
@@ -134,6 +134,10 @@ SRCS+=	onoe.c
 SRCS+=	amrr.c
 .endif
 
+# DFS
+.PATH: ${.CURDIR}/../../dev/ath/ath_dfs/null
+SRCS+=	dfs_null.c
+
 CFLAGS+=  -I. -I${.CURDIR}/../../dev/ath -I${.CURDIR}/../../dev/ath/ath_hal
 
 opt_ah.h: