[RFC v6 wireless-next 4/4] wifi: mac80211_hwsim: background CAC support

[Janusz Dziedzic <janusz.dziedzic@gmail.com>]

Report background CAC support and add allow
to cancel background CAC and simulate radar.

echo cancel > /sys/kernel/debug/ieee80211/phy2/hwsim/dfs_background_cac
echo radar > /sys/kernel/debug/ieee80211/phy2/hwsim/dfs_background_cac

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@gmail.com>
---
 drivers/net/wireless/virtual/mac80211_hwsim.c | 68 ++++++++++++++++++-
 1 file changed, 67 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/virtual/mac80211_hwsim.c b/drivers/net/wireless/virtual/mac80211_hwsim.c
index 4d9f5f87e814..682cfc413c9b 100644
--- a/drivers/net/wireless/virtual/mac80211_hwsim.c
+++ b/drivers/net/wireless/virtual/mac80211_hwsim.c
@@ -73,6 +73,10 @@ static bool multi_radio;
 module_param(multi_radio, bool, 0444);
 MODULE_PARM_DESC(multi_radio, "Support Multiple Radios per wiphy");
 
+static bool background_radar = true;
+module_param(background_radar, bool, 0444);
+MODULE_PARM_DESC(background_radar, "Support background radar/CAC");
+
 /**
  * enum hwsim_regtest - the type of regulatory tests we offer
  *
@@ -715,6 +719,7 @@ struct mac80211_hwsim_data {
 	} ps;
 	bool ps_poll_pending;
 	struct dentry *debugfs;
+	struct cfg80211_chan_def radar_background_chandef;
 
 	atomic_t pending_cookie;
 	struct sk_buff_head pending;	/* packets pending */
@@ -1164,6 +1169,41 @@ static int hwsim_write_simulate_radar(void *dat, u64 val)
 DEFINE_DEBUGFS_ATTRIBUTE(hwsim_simulate_radar, NULL,
 			 hwsim_write_simulate_radar, "%llu\n");
 
+static ssize_t hwsim_background_cac_write(struct file *file,
+					  const char __user *user_buf,
+					  size_t count, loff_t *ppos)
+{
+	struct mac80211_hwsim_data *data = file->private_data;
+	char buf[8] = {};
+
+	if (count >= sizeof(buf))
+		return -EINVAL;
+
+	if (copy_from_user(buf, user_buf, count))
+		return -EFAULT;
+
+	/* Check if background radar channel is configured */
+	if (!data->radar_background_chandef.chan)
+		return -ENOENT;
+
+	if (sysfs_streq(buf, "radar"))
+		cfg80211_background_radar_event(data->hw->wiphy,
+						&data->radar_background_chandef,
+						GFP_KERNEL);
+	else if (sysfs_streq(buf, "cancel"))
+		cfg80211_background_cac_abort(data->hw->wiphy);
+	else
+		return -EINVAL;
+
+	return count;
+}
+
+static const struct file_operations hwsim_background_cac_ops = {
+	.write = hwsim_background_cac_write,
+	.open = simple_open,
+	.llseek = default_llseek,
+};
+
 static int hwsim_fops_group_read(void *dat, u64 *val)
 {
 	struct mac80211_hwsim_data *data = dat;
@@ -4154,6 +4194,23 @@ static int mac80211_hwsim_change_nan_config(struct ieee80211_hw *hw,
 	return 0;
 }
 
+static int mac80211_hwsim_set_radar_background(struct ieee80211_hw *hw,
+					       struct cfg80211_chan_def *chan)
+{
+	struct mac80211_hwsim_data *data = hw->priv;
+
+	if (!background_radar)
+		return -EOPNOTSUPP;
+
+	if (chan)
+		data->radar_background_chandef = *chan;
+	else
+		memset(&data->radar_background_chandef, 0,
+		       sizeof(data->radar_background_chandef));
+
+	return 0;
+}
+
 #ifdef CONFIG_MAC80211_DEBUGFS
 #define HWSIM_DEBUGFS_OPS					\
 	.link_add_debugfs = mac80211_hwsim_link_add_debugfs,
@@ -4189,6 +4246,7 @@ static int mac80211_hwsim_change_nan_config(struct ieee80211_hw *hw,
 	.start_nan = mac80211_hwsim_start_nan,                  \
 	.stop_nan = mac80211_hwsim_stop_nan,                    \
 	.nan_change_conf = mac80211_hwsim_change_nan_config,    \
+	.set_radar_background = mac80211_hwsim_set_radar_background, \
 	HWSIM_DEBUGFS_OPS
 
 #define HWSIM_NON_MLO_OPS					\
@@ -5794,6 +5852,9 @@ static int mac80211_hwsim_new_radio(struct genl_info *info,
 
 	wiphy_ext_feature_set(hw->wiphy,
 			      NL80211_EXT_FEATURE_DFS_CONCURRENT);
+	if (background_radar)
+		wiphy_ext_feature_set(hw->wiphy,
+				      NL80211_EXT_FEATURE_RADAR_BACKGROUND);
 
 	if (param->no_vif)
 		ieee80211_hw_set(hw, NO_AUTO_VIF);
@@ -5828,10 +5889,15 @@ static int mac80211_hwsim_new_radio(struct genl_info *info,
 			    &hwsim_fops_group);
 	debugfs_create_file("rx_rssi", 0666, data->debugfs, data,
 			    &hwsim_fops_rx_rssi);
-	if (!data->use_chanctx)
+	if (!data->use_chanctx) {
 		debugfs_create_file("dfs_simulate_radar", 0222,
 				    data->debugfs,
 				    data, &hwsim_simulate_radar);
+		if (background_radar)
+			debugfs_create_file("dfs_background_cac", 0200,
+					    data->debugfs,
+					    data, &hwsim_background_cac_ops);
+	}
 
 	if (param->pmsr_capa) {
 		data->pmsr_capa = *param->pmsr_capa;
-- 
2.43.0