wifi: mt76: mt7996: fix the behavior of radar detection

RDD_DET_MODE is a firmware command intended for testing and does not
pause TX after radar detection, so remove it from the normal flow;
instead, use the MAC_ENABLE_CTRL firmware command to resume TX after
the radar-triggered channel switch completes.

Fixes: 1529e335f93d ("wifi: mt76: mt7996: rework radar HWRDD idx")
Co-developed-by: Shayne Chen <[email protected]>
Signed-off-by: Shayne Chen <[email protected]>
Signed-off-by: StanleyYP Wang <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Felix Fietkau <[email protected]>

mt7996/mac.c

@@ -2973,7 +2973,7 @@ static void mt7996_dfs_stop_radar_detector(struct mt7996_phy *phy)
 
 static int mt7996_dfs_start_rdd(struct mt7996_dev *dev, int rdd_idx)
 {
-	int err, region;
+	int region;
 
 	switch (dev->mt76.region) {
 	case NL80211_DFS_ETSI:
@@ -2988,11 +2988,7 @@ static int mt7996_dfs_start_rdd(struct mt7996_dev *dev, int rdd_idx)
 		break;
 	}
 
-	err = mt7996_mcu_rdd_cmd(dev, RDD_START, rdd_idx, region);
+	return mt7996_mcu_rdd_cmd(dev, RDD_START, rdd_idx, region);
-	if (err < 0)
-		return err;
-
-	return mt7996_mcu_rdd_cmd(dev, RDD_DET_MODE, rdd_idx, 1);
 }
 
 static int mt7996_dfs_start_radar_detector(struct mt7996_phy *phy)

mt7996/main.c

@@ -79,6 +79,7 @@ static void mt7996_stop_phy(struct mt7996_phy *phy)
 
 	mutex_lock(&dev->mt76.mutex);
 
+	mt7996_mcu_rdd_resume_tx(phy);
 	mt7996_mcu_set_radio_en(phy, false);
 
 	clear_bit(MT76_STATE_RUNNING, &phy->mt76->state);
@@ -953,6 +954,24 @@ mt7996_channel_switch_beacon(struct ieee80211_hw *hw,
 	mutex_unlock(&dev->mt76.mutex);
 }
 
+static int
+mt7996_post_channel_switch(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+			   struct ieee80211_bss_conf *link_conf)
+{
+	struct cfg80211_chan_def *chandef = &link_conf->chanreq.oper;
+	struct mt7996_dev *dev = mt7996_hw_dev(hw);
+	struct mt7996_phy *phy = mt7996_band_phy(dev, chandef->chan->band);
+	int ret;
+
+	mutex_lock(&dev->mt76.mutex);
+
+	ret = mt7996_mcu_rdd_resume_tx(phy);
+
+	mutex_unlock(&dev->mt76.mutex);
+
+	return ret;
+}
+
 static int
 mt7996_mac_sta_init_link(struct mt7996_dev *dev,
 			 struct ieee80211_bss_conf *link_conf,
@@ -2326,6 +2345,7 @@ const struct ieee80211_ops mt7996_ops = {
 	.release_buffered_frames = mt76_release_buffered_frames,
 	.get_txpower = mt7996_get_txpower,
 	.channel_switch_beacon = mt7996_channel_switch_beacon,
+	.post_channel_switch = mt7996_post_channel_switch,
 	.get_stats = mt7996_get_stats,
 	.get_et_sset_count = mt7996_get_et_sset_count,
 	.get_et_stats = mt7996_get_et_stats,

mt7996/mcu.c

@@ -520,24 +520,32 @@ mt7996_mcu_rx_radar_detected(struct mt7996_dev *dev, struct sk_buff *skb)
 		break;
 	case MT_RDD_IDX_BACKGROUND:
 		if (!dev->rdd2_phy)
-			return;
+			goto err;
 		mphy = dev->rdd2_phy->mt76;
 		break;
 	default:
-		dev_err(dev->mt76.dev, "Unknown RDD idx %d\n", r->rdd_idx);
+		goto err;
-		return;
 	}
 
 	if (!mphy)
-		return;
+		goto err;
 
-	if (r->rdd_idx == MT_RDD_IDX_BACKGROUND)
+	if (r->rdd_idx == MT_RDD_IDX_BACKGROUND) {
 		cfg80211_background_radar_event(mphy->hw->wiphy,
 						&dev->rdd2_chandef,
 						GFP_ATOMIC);
-	else
+	} else {
+		struct mt7996_phy *phy = mphy->priv;
+
+		phy->rdd_tx_paused = true;
 		ieee80211_radar_detected(mphy->hw, NULL);
+	}
 	dev->hw_pattern++;
+
+	return;
+
+err:
+	dev_err(dev->mt76.dev, "Invalid RDD idx %d\n", r->rdd_idx);
 }
 
 static void
@@ -4610,6 +4618,35 @@ int mt7996_mcu_set_radio_en(struct mt7996_phy *phy, bool enable)
 				 &req, sizeof(req), true);
 }
 
+int mt7996_mcu_rdd_resume_tx(struct mt7996_phy *phy)
+{
+	struct {
+		u8 band_idx;
+		u8 _rsv[3];
+
+		__le16 tag;
+		__le16 len;
+		u8 mac_enable;
+		u8 _rsv2[3];
+	} __packed req = {
+		.band_idx = phy->mt76->band_idx,
+		.tag = cpu_to_le16(UNI_BAND_CONFIG_MAC_ENABLE_CTRL),
+		.len = cpu_to_le16(sizeof(req) - 4),
+		.mac_enable = 2,
+	};
+	int ret;
+
+	if (!phy->rdd_tx_paused)
+		return 0;
+
+	ret = mt76_mcu_send_msg(&phy->dev->mt76, MCU_WM_UNI_CMD(BAND_CONFIG),
+				&req, sizeof(req), true);
+	if (!ret)
+		phy->rdd_tx_paused = false;
+
+	return ret;
+}
+
 int mt7996_mcu_rdd_cmd(struct mt7996_dev *dev, int cmd, u8 rdd_idx, u8 val)
 {
 	struct {

mt7996/mcu.h

@@ -835,6 +835,7 @@ enum {
 enum {
 	UNI_BAND_CONFIG_RADIO_ENABLE,
 	UNI_BAND_CONFIG_RTS_THRESHOLD = 0x08,
+	UNI_BAND_CONFIG_MAC_ENABLE_CTRL = 0x0c,
 };
 
 enum {

mt7996/mt7996.h

@@ -377,6 +377,7 @@ struct mt7996_phy {
 
 	bool has_aux_rx;
 	bool counter_reset;
+	bool rdd_tx_paused;
 };
 
 struct mt7996_dev {
@@ -726,6 +727,7 @@ int mt7996_mcu_get_temperature(struct mt7996_phy *phy);
 int mt7996_mcu_set_thermal_throttling(struct mt7996_phy *phy, u8 state);
 int mt7996_mcu_set_thermal_protect(struct mt7996_phy *phy, bool enable);
 int mt7996_mcu_set_txpower_sku(struct mt7996_phy *phy);
+int mt7996_mcu_rdd_resume_tx(struct mt7996_phy *phy);
 int mt7996_mcu_rdd_cmd(struct mt7996_dev *dev, int cmd, u8 rdd_idx, u8 val);
 int mt7996_mcu_rdd_background_enable(struct mt7996_phy *phy,
 				     struct cfg80211_chan_def *chandef);