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>

3 files changed, 45 insertions, 8 deletions

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 @@ function parse_reg_rule()
 	units = $8
 	sub(/\)/, "", units)
 	sub(/,/, "", units)
+	dfs_cac = $9
 	if (units == "mW") {
 		if (power == 100) {
 			power = 20
@@ -78,7 +79,12 @@ function parse_reg_rule()
 		} 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 @@ function parse_reg_rule()
 
 	}
 	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 @@ static int nl80211_msg_put_channel(struct sk_buff *msg,
 			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 @@ static const struct nla_policy reg_rule_policy[NL80211_REG_RULE_ATTR_MAX + 1] =
 	[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 @@ static int parse_reg_rule(struct nlattr *tb[],
 		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 @@ static int nl80211_get_reg(struct sk_buff *skb, struct genl_info *info)
 		    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 @@ static int reg_rules_intersect(const struct ieee80211_regdomain *rd1,
 	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 @@ static void handle_channel(struct wiphy *wiphy,
 		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 @@ static void print_rd_rules(const struct ieee80211_regdomain *rd)
 	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 @@ static void print_rd_rules(const struct ieee80211_regdomain *rd)
 			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);
 	}
 }