mac80211_hwsim: Add iface comb for DFS

Add iface combination that will allow DFS
support. Add also debugfs dfs_simulate_radar
file that can be used to simulate radar event.
This could be useful for mac80211/cfg80211/
regulatory/hostap code testing without real HW.
Signed-off-by: NJanusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

drivers/net/wireless/mac80211_hwsim.c

@@ -1889,6 +1889,17 @@ static int hwsim_fops_ps_write(void *dat, u64 val)
 DEFINE_SIMPLE_ATTRIBUTE(hwsim_fops_ps, hwsim_fops_ps_read, hwsim_fops_ps_write,
 			"%llu\n");
 
+static int hwsim_write_simulate_radar(void *dat, u64 val)
+{
+	struct mac80211_hwsim_data *data = dat;
+
+	ieee80211_radar_detected(data->hw);
+
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(hwsim_simulate_radar, NULL,
+			hwsim_write_simulate_radar, "%llu\n");
 
 static int hwsim_fops_group_read(void *dat, u64 *val)
 {
@@ -2190,11 +2201,28 @@ static const struct ieee80211_iface_limit hwsim_if_limits[] = {
 	{ .max = 1, .types = BIT(NL80211_IFTYPE_P2P_DEVICE) },
 };
 
-static struct ieee80211_iface_combination hwsim_if_comb = {
-	.limits = hwsim_if_limits,
-	.n_limits = ARRAY_SIZE(hwsim_if_limits),
-	.max_interfaces = 2048,
-	.num_different_channels = 1,
+static const struct ieee80211_iface_limit hwsim_if_dfs_limits[] = {
+	{ .max = 8, .types = BIT(NL80211_IFTYPE_AP) },
+};
+
+static struct ieee80211_iface_combination hwsim_if_comb[] = {
+	{
+		.limits = hwsim_if_limits,
+		.n_limits = ARRAY_SIZE(hwsim_if_limits),
+		.max_interfaces = 2048,
+		.num_different_channels = 1,
+	},
+	{
+		.limits = hwsim_if_dfs_limits,
+		.n_limits = ARRAY_SIZE(hwsim_if_dfs_limits),
+		.max_interfaces = 8,
+		.num_different_channels = 1,
+		.radar_detect_widths = BIT(NL80211_CHAN_WIDTH_20_NOHT) |
+				       BIT(NL80211_CHAN_WIDTH_20) |
+				       BIT(NL80211_CHAN_WIDTH_40) |
+				       BIT(NL80211_CHAN_WIDTH_80) |
+				       BIT(NL80211_CHAN_WIDTH_160),
+	}
 };
 
 static int __init init_mac80211_hwsim(void)
@@ -2212,7 +2240,7 @@ static int __init init_mac80211_hwsim(void)
 		return -EINVAL;
 
 	if (channels > 1) {
-		hwsim_if_comb.num_different_channels = channels;
+		hwsim_if_comb[0].num_different_channels = channels;
 		mac80211_hwsim_ops.hw_scan = mac80211_hwsim_hw_scan;
 		mac80211_hwsim_ops.cancel_hw_scan =
 			mac80211_hwsim_cancel_hw_scan;
@@ -2292,13 +2320,15 @@ static int __init init_mac80211_hwsim(void)
 		hw->wiphy->n_addresses = 2;
 		hw->wiphy->addresses = data->addresses;
 
-		hw->wiphy->iface_combinations = &hwsim_if_comb;
-		hw->wiphy->n_iface_combinations = 1;
+		hw->wiphy->iface_combinations = hwsim_if_comb;
+		hw->wiphy->n_iface_combinations = ARRAY_SIZE(hwsim_if_comb);
 
 		if (channels > 1) {
 			hw->wiphy->max_scan_ssids = 255;
 			hw->wiphy->max_scan_ie_len = IEEE80211_MAX_DATA_LEN;
 			hw->wiphy->max_remain_on_channel_duration = 1000;
+			/* For channels > 1 DFS is not allowed */
+			hw->wiphy->n_iface_combinations = 1;
 		}
 
 		INIT_DELAYED_WORK(&data->roc_done, hw_roc_done);
@@ -2534,6 +2564,10 @@ static int __init init_mac80211_hwsim(void)
 				    &hwsim_fops_ps);
 		debugfs_create_file("group", 0666, data->debugfs, data,
 				    &hwsim_fops_group);
+		if (channels == 1)
+			debugfs_create_file("dfs_simulate_radar", 0222,
+					    data->debugfs,
+					    data, &hwsim_simulate_radar);
 
 		tasklet_hrtimer_init(&data->beacon_timer,
 				     mac80211_hwsim_beacon,