cfg80211: regulatory: allow getting DFS CAC time from userspace

Introduce DFS CAC time as a regd param, configured per REG_RULE and
set per channel in cfg80211. DFS CAC time is close connected with
regulatory database configuration. Instead of using hardcoded values,
get DFS CAC time form regulatory database. Pass DFS CAC time to user
mode (mainly for iw reg get, iw list, iw info). Allow setting DFS CAC
time via CRDA. Add support for internal regulatory database.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
[rewrap commit log]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/wireless/genregdb.awk b/net/wireless/genregdb.awk
index fdfd3f0..b35da8d 100644
--- a/net/wireless/genregdb.awk
+++ b/net/wireless/genregdb.awk
@@ -66,6 +66,7 @@
 	units = $8
 	sub(/\)/, "", units)
 	sub(/,/, "", units)
+	dfs_cac = $9
 	if (units == "mW") {
 		if (power == 100) {
 			power = 20
@@ -78,7 +79,12 @@
 		} else {
 			print "Unknown power value in database!"
 		}
+	} else {
+		dfs_cac = $8
 	}
+	sub(/,/, "", dfs_cac)
+	sub(/\(/, "", dfs_cac)
+	sub(/\)/, "", dfs_cac)
 	flagstr = ""
 	for (i=8; i<=NF; i++)
 		flagstr = flagstr $i
@@ -111,7 +117,7 @@
 
 	}
 	flags = flags "0"
-	printf "\t\tREG_RULE(%d, %d, %d, %d, %d, %s),\n", start, end, bw, gain, power, flags
+	printf "\t\tREG_RULE_EXT(%d, %d, %d, %d, %d, %d, %s),\n", start, end, bw, gain, power, dfs_cac, flags
 	rules++
 }
 
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 2c38b28..9f7ebf9 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -593,6 +593,10 @@
 			if (nla_put_u32(msg, NL80211_FREQUENCY_ATTR_DFS_TIME,
 					time))
 				goto nla_put_failure;
+			if (nla_put_u32(msg,
+					NL80211_FREQUENCY_ATTR_DFS_CAC_TIME,
+					chan->dfs_cac_ms))
+				goto nla_put_failure;
 		}
 	}
 
@@ -4614,6 +4618,7 @@
 	[NL80211_ATTR_FREQ_RANGE_MAX_BW]	= { .type = NLA_U32 },
 	[NL80211_ATTR_POWER_RULE_MAX_ANT_GAIN]	= { .type = NLA_U32 },
 	[NL80211_ATTR_POWER_RULE_MAX_EIRP]	= { .type = NLA_U32 },
+	[NL80211_ATTR_DFS_CAC_TIME]		= { .type = NLA_U32 },
 };
 
 static int parse_reg_rule(struct nlattr *tb[],
@@ -4649,6 +4654,10 @@
 		power_rule->max_antenna_gain =
 			nla_get_u32(tb[NL80211_ATTR_POWER_RULE_MAX_ANT_GAIN]);
 
+	if (tb[NL80211_ATTR_DFS_CAC_TIME])
+		reg_rule->dfs_cac_ms =
+			nla_get_u32(tb[NL80211_ATTR_DFS_CAC_TIME]);
+
 	return 0;
 }
 
@@ -5136,7 +5145,9 @@
 		    nla_put_u32(msg, NL80211_ATTR_POWER_RULE_MAX_ANT_GAIN,
 				power_rule->max_antenna_gain) ||
 		    nla_put_u32(msg, NL80211_ATTR_POWER_RULE_MAX_EIRP,
-				power_rule->max_eirp))
+				power_rule->max_eirp) ||
+		    nla_put_u32(msg, NL80211_ATTR_DFS_CAC_TIME,
+				reg_rule->dfs_cac_ms))
 			goto nla_put_failure_rcu;
 
 		nla_nest_end(msg, nl_reg_rule);
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 651404c..b95e9cf 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -756,6 +756,9 @@
 	power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
 		power_rule2->max_antenna_gain);
 
+	intersected_rule->dfs_cac_ms = max(rule1->dfs_cac_ms,
+					   rule2->dfs_cac_ms);
+
 	if (!is_valid_reg_rule(intersected_rule))
 		return -EINVAL;
 
@@ -1078,6 +1081,14 @@
 		min_t(int, chan->orig_mag,
 		      MBI_TO_DBI(power_rule->max_antenna_gain));
 	chan->max_reg_power = (int) MBM_TO_DBM(power_rule->max_eirp);
+
+	if (chan->flags & IEEE80211_CHAN_RADAR) {
+		if (reg_rule->dfs_cac_ms)
+			chan->dfs_cac_ms = reg_rule->dfs_cac_ms;
+		else
+			chan->dfs_cac_ms = IEEE80211_DFS_MIN_CAC_TIME_MS;
+	}
+
 	if (chan->orig_mpwr) {
 		/*
 		 * Devices that use REGULATORY_COUNTRY_IE_FOLLOW_POWER
@@ -2256,9 +2267,9 @@
 	const struct ieee80211_reg_rule *reg_rule = NULL;
 	const struct ieee80211_freq_range *freq_range = NULL;
 	const struct ieee80211_power_rule *power_rule = NULL;
-	char bw[32];
+	char bw[32], cac_time[32];
 
-	pr_info("  (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
+	pr_info("  (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp), (dfs_cac_time)\n");
 
 	for (i = 0; i < rd->n_reg_rules; i++) {
 		reg_rule = &rd->reg_rules[i];
@@ -2273,23 +2284,32 @@
 			snprintf(bw, sizeof(bw), "%d KHz",
 				 freq_range->max_bandwidth_khz);
 
+		if (reg_rule->flags & NL80211_RRF_DFS)
+			scnprintf(cac_time, sizeof(cac_time), "%u s",
+				  reg_rule->dfs_cac_ms/1000);
+		else
+			scnprintf(cac_time, sizeof(cac_time), "N/A");
+
+
 		/*
 		 * There may not be documentation for max antenna gain
 		 * in certain regions
 		 */
 		if (power_rule->max_antenna_gain)
-			pr_info("  (%d KHz - %d KHz @ %s), (%d mBi, %d mBm)\n",
+			pr_info("  (%d KHz - %d KHz @ %s), (%d mBi, %d mBm), (%s)\n",
 				freq_range->start_freq_khz,
 				freq_range->end_freq_khz,
 				bw,
 				power_rule->max_antenna_gain,
-				power_rule->max_eirp);
+				power_rule->max_eirp,
+				cac_time);
 		else
-			pr_info("  (%d KHz - %d KHz @ %s), (N/A, %d mBm)\n",
+			pr_info("  (%d KHz - %d KHz @ %s), (N/A, %d mBm), (%s)\n",
 				freq_range->start_freq_khz,
 				freq_range->end_freq_khz,
 				bw,
-				power_rule->max_eirp);
+				power_rule->max_eirp,
+				cac_time);
 	}
 }