nl80211/cfg80211: add radar detection command/event

Add new NL80211_CMD_RADAR_DETECT, which starts the Channel
Availability Check (CAC). This command will also notify the
usermode about events (CAC finished, CAC aborted, radar
detected, NOP finished).
Once radar detection has started it should continuously
monitor for radars as long as the channel is active.

This patch enables DFS for AP mode in nl80211/cfg80211.

Based on original patch by Victor Goldenshtein <victorg@ti.com>

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
[remove WIPHY_FLAG_HAS_RADAR_DETECT again -- my mistake]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/net/wireless/core.h b/net/wireless/core.h
index 949c9573d8d7..3aec0e429d8a 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -86,6 +86,8 @@ struct cfg80211_registered_device {
 
         struct cfg80211_wowlan *wowlan;
 
+        struct delayed_work dfs_update_channels_wk;
+
         /* must be last because of the way we do wiphy_priv(),
          * and it should at least be aligned to NETDEV_ALIGN */
         struct wiphy wiphy __aligned(NETDEV_ALIGN);
@@ -431,6 +433,22 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
                                  enum cfg80211_chan_mode chanmode,
                                  u8 radar_detect);
 
+/**
+ * cfg80211_chandef_dfs_required - checks if radar detection is required
+ * @wiphy: the wiphy to validate against
+ * @chandef: the channel definition to check
+ * Return: 1 if radar detection is required, 0 if it is not, < 0 on error
+ */
+int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
+                                  const struct cfg80211_chan_def *c);
+
+void cfg80211_set_dfs_state(struct wiphy *wiphy,
+                            const struct cfg80211_chan_def *chandef,
+                            enum nl80211_dfs_state dfs_state);
+
+void cfg80211_dfs_channels_update_work(struct work_struct *work);
+
+
 static inline int
 cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
                               struct wireless_dev *wdev,
@@ -457,6 +475,16 @@ cfg80211_can_use_chan(struct cfg80211_registered_device *rdev,
                                             chan, chanmode, 0);
 }
 
+static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
+{
+        unsigned long end = jiffies;
+
+        if (end >= start)
+                return jiffies_to_msecs(end - start);
+
+        return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
+}
+
 void
 cfg80211_get_chan_state(struct wireless_dev *wdev,
                         struct ieee80211_channel **chan,