mt76: fix dfs state issue with 160 MHz channels

When operating on a mix of DFS and non-DFS channels, the driver only checks
the CAC status of the control channel. This causes beacons/tx to fail if the
control channel is on a non-DFS channel.
Fix this by calling cfg80211_reg_can_beacon to determine the DFS status of
all affected channels
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mac80211.c

@@ -1658,7 +1658,7 @@ enum mt76_dfs_state mt76_phy_dfs_state(struct mt76_phy *phy)
 		return MT_DFS_STATE_DISABLED;
 	}
 
-	if (phy->chandef.chan->dfs_state != NL80211_DFS_AVAILABLE)
+	if (!cfg80211_reg_can_beacon(hw->wiphy, &phy->chandef, NL80211_IFTYPE_AP))
 		return MT_DFS_STATE_CAC;
 
 	return MT_DFS_STATE_ACTIVE;

drivers/net/wireless/mediatek/mt76/mt7615/mcu.c

@@ -2151,10 +2151,12 @@ int mt7615_mcu_set_chan_info(struct mt7615_phy *phy, int cmd)
 		.center_chan2 = ieee80211_frequency_to_channel(freq2),
 	};
 
-	if (phy->mt76->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
+	if (cmd == MCU_EXT_CMD(SET_RX_PATH))
+		req.switch_reason = CH_SWITCH_NORMAL;
+	else if (phy->mt76->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
 		req.switch_reason = CH_SWITCH_SCAN_BYPASS_DPD;
-	else if ((chandef->chan->flags & IEEE80211_CHAN_RADAR) &&
-		 chandef->chan->dfs_state != NL80211_DFS_AVAILABLE)
+	else if (!cfg80211_reg_can_beacon(phy->mt76->hw->wiphy, chandef,
+					  NL80211_IFTYPE_AP))
 		req.switch_reason = CH_SWITCH_DFS;
 	else
 		req.switch_reason = CH_SWITCH_NORMAL;

drivers/net/wireless/mediatek/mt76/mt7915/mcu.c

@@ -2811,10 +2811,12 @@ int mt7915_mcu_set_chan_info(struct mt7915_phy *phy, int cmd)
 	}
 #endif
 
-	if (phy->mt76->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
+	if (cmd == MCU_EXT_CMD(SET_RX_PATH))
+		req.switch_reason = CH_SWITCH_NORMAL;
+	else if (phy->mt76->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
 		req.switch_reason = CH_SWITCH_SCAN_BYPASS_DPD;
-	else if (phy->mt76->hw->conf.radar_enabled &&
-		 chandef->chan->dfs_state != NL80211_DFS_AVAILABLE)
+	else if (!cfg80211_reg_can_beacon(phy->mt76->hw->wiphy, chandef,
+					  NL80211_IFTYPE_AP))
 		req.switch_reason = CH_SWITCH_DFS;
 	else
 		req.switch_reason = CH_SWITCH_NORMAL;

drivers/net/wireless/mediatek/mt76/mt7921/mcu.c

@@ -863,10 +863,12 @@ int mt7921_mcu_set_chan_info(struct mt7921_phy *phy, int cmd)
 	else
 		req.channel_band = chandef->chan->band;
 
-	if (dev->mt76.hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
+	if (cmd == MCU_EXT_CMD(SET_RX_PATH))
+		req.switch_reason = CH_SWITCH_NORMAL;
+	else if (dev->mt76.hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
 		req.switch_reason = CH_SWITCH_SCAN_BYPASS_DPD;
-	else if ((chandef->chan->flags & IEEE80211_CHAN_RADAR) &&
-		 chandef->chan->dfs_state != NL80211_DFS_AVAILABLE)
+	else if (!cfg80211_reg_can_beacon(dev->mt76.hw->wiphy, chandef,
+					  NL80211_IFTYPE_AP))
 		req.switch_reason = CH_SWITCH_DFS;
 	else
 		req.switch_reason = CH_SWITCH_NORMAL;