cfg80211: DFS get CAC time from regulatory database

Send Channel Availability Check time as a parameter
of start_radar_detection() callback.
Get CAC time from regulatory database.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

5 files changed, 72 insertions, 6 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 1acb29109b45..80534f524fd6 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -2914,11 +2914,11 @@ static int ieee80211_cancel_remain_on_channel(struct wiphy *wiphy,
 
 static int ieee80211_start_radar_detection(struct wiphy *wiphy,
                                            struct net_device *dev,
-                                           struct cfg80211_chan_def *chandef)
+                                           struct cfg80211_chan_def *chandef,
+                                           u32 cac_time_ms)
 {
         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
         struct ieee80211_local *local = sdata->local;
-        unsigned long timeout;
         int err;
 
         mutex_lock(&local->mtx);
@@ -2937,9 +2937,9 @@ static int ieee80211_start_radar_detection(struct wiphy *wiphy,
         if (err)
                 goto out_unlock;
 
-        timeout = msecs_to_jiffies(IEEE80211_DFS_MIN_CAC_TIME_MS);
         ieee80211_queue_delayed_work(&sdata->local->hw,
-                                     &sdata->dfs_cac_timer_work, timeout);
+                                     &sdata->dfs_cac_timer_work,
+                                     msecs_to_jiffies(cac_time_ms));
 
  out_unlock:
         mutex_unlock(&local->mtx);
diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 5946450c5406..8659d5cee2a6 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -490,6 +490,62 @@ static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
         return r;
 }
 
+static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
+                                                    u32 center_freq,
+                                                    u32 bandwidth)
+{
+        struct ieee80211_channel *c;
+        u32 start_freq, end_freq, freq;
+        unsigned int dfs_cac_ms = 0;
+
+        start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
+        end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
+
+        for (freq = start_freq; freq <= end_freq; freq += 20) {
+                c = ieee80211_get_channel(wiphy, freq);
+                if (!c)
+                        return 0;
+
+                if (c->flags & IEEE80211_CHAN_DISABLED)
+                        return 0;
+
+                if (!(c->flags & IEEE80211_CHAN_RADAR))
+                        continue;
+
+                if (c->dfs_cac_ms > dfs_cac_ms)
+                        dfs_cac_ms = c->dfs_cac_ms;
+        }
+
+        return dfs_cac_ms;
+}
+
+unsigned int
+cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
+                              const struct cfg80211_chan_def *chandef)
+{
+        int width;
+        unsigned int t1 = 0, t2 = 0;
+
+        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
+                return 0;
+
+        width = cfg80211_chandef_get_width(chandef);
+        if (width < 0)
+                return 0;
+
+        t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
+                                             chandef->center_freq1,
+                                             width);
+
+        if (!chandef->center_freq2)
+                return t1;
+
+        t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
+                                             chandef->center_freq2,
+                                             width);
+
+        return max(t1, t2);
+}
 
 static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
                                         u32 center_freq, u32 bandwidth,
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 40683004d523..64fde38c1a7e 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -402,6 +402,9 @@ void cfg80211_set_dfs_state(struct wiphy *wiphy,
 
 void cfg80211_dfs_channels_update_work(struct work_struct *work);
 
+unsigned int
+cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
+                              const struct cfg80211_chan_def *chandef);
 
 static inline int
 cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index d47c9d127b1e..c52ff59a3e96 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -778,7 +778,7 @@ void cfg80211_cac_event(struct net_device *netdev,
         switch (event) {
         case NL80211_RADAR_CAC_FINISHED:
                 timeout = wdev->cac_start_time +
-                          msecs_to_jiffies(IEEE80211_DFS_MIN_CAC_TIME_MS);
+                          msecs_to_jiffies(wdev->cac_time_ms);
                 WARN_ON(!time_after_eq(jiffies, timeout));
                 cfg80211_set_dfs_state(wiphy, chandef, NL80211_DFS_AVAILABLE);
                 break;
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 9f7ebf94a050..8fa02a3fa7f7 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5779,6 +5779,7 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
         struct wireless_dev *wdev = dev->ieee80211_ptr;
         struct cfg80211_chan_def chandef;
         enum nl80211_dfs_regions dfs_region;
+        unsigned int cac_time_ms;
         int err;
 
         dfs_region = reg_get_dfs_region(wdev->wiphy);
@@ -5814,11 +5815,17 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
         if (err)
                 return err;
 
-        err = rdev->ops->start_radar_detection(&rdev->wiphy, dev, &chandef);
+        cac_time_ms = cfg80211_chandef_dfs_cac_time(&rdev->wiphy, &chandef);
+        if (WARN_ON(!cac_time_ms))
+                cac_time_ms = IEEE80211_DFS_MIN_CAC_TIME_MS;
+
+        err = rdev->ops->start_radar_detection(&rdev->wiphy, dev, &chandef,
+                                               cac_time_ms);
         if (!err) {
                 wdev->chandef = chandef;
                 wdev->cac_started = true;
                 wdev->cac_start_time = jiffies;
+                wdev->cac_time_ms = cac_time_ms;
         }
         return err;
 }