mt76: mt76x02: disable ED/CCA by default

This feature has been reported to cause stability issues on several systems.
Disable it until it has been fixed and verified. It can still be enabled
through debugfs
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt76x02.h

@@ -118,6 +118,7 @@ struct mt76x02_dev {
 	unsigned long ed_trigger_timeout;
 	bool ed_tx_blocked;
 	bool ed_monitor;
+	u8 ed_monitor_enabled;
 	u8 ed_monitor_learning;
 	u8 ed_trigger;
 	u8 ed_silent;

drivers/net/wireless/mediatek/mt76/mt76x02_debugfs.c

@@ -116,6 +116,32 @@ static int read_agc(struct seq_file *file, void *data)
 	return 0;
 }
 
+static int
+mt76_edcca_set(void *data, u64 val)
+{
+	struct mt76x02_dev *dev = data;
+	enum nl80211_dfs_regions region = dev->dfs_pd.region;
+
+	dev->ed_monitor_enabled = !!val;
+	dev->ed_monitor = dev->ed_monitor_enabled &&
+			  region == NL80211_DFS_ETSI;
+	mt76x02_edcca_init(dev, true);
+
+	return 0;
+}
+
+static int
+mt76_edcca_get(void *data, u64 *val)
+{
+	struct mt76x02_dev *dev = data;
+
+	*val = dev->ed_monitor_enabled;
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(fops_edcca, mt76_edcca_get, mt76_edcca_set,
+			 "%lld\n");
+
 void mt76x02_init_debugfs(struct mt76x02_dev *dev)
 {
 	struct dentry *dir;
@@ -127,6 +153,7 @@ void mt76x02_init_debugfs(struct mt76x02_dev *dev)
 	debugfs_create_u8("temperature", 0400, dir, &dev->cal.temp);
 	debugfs_create_bool("tpc", 0600, dir, &dev->enable_tpc);
 
+	debugfs_create_file("edcca", 0400, dir, dev, &fops_edcca);
 	debugfs_create_file("ampdu_stat", 0400, dir, dev, &fops_ampdu_stat);
 	debugfs_create_file("dfs_stats", 0400, dir, dev, &fops_dfs_stat);
 	debugfs_create_devm_seqfile(dev->mt76.dev, "txpower", dir,

drivers/net/wireless/mediatek/mt76/mt76x02_dfs.c

@@ -885,7 +885,8 @@ mt76x02_dfs_set_domain(struct mt76x02_dev *dev,
 	if (dfs_pd->region != region) {
 		tasklet_disable(&dfs_pd->dfs_tasklet);
 
-		dev->ed_monitor = region == NL80211_DFS_ETSI;
+		dev->ed_monitor = dev->ed_monitor_enabled &&
+				  region == NL80211_DFS_ETSI;
 		mt76x02_edcca_init(dev, true);
 
 		dfs_pd->region = region;