wifi: mt76: mt7925: add auto regdomain switch support

Implement 802.11d-based automatic regulatory domain switching to
dynamically determine the regulatory domain at runtime.

Signed-off-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com>
Link: https://patch.msgid.link/20251031090352.1400079-6-mingyen.hsieh@mediatek.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7925/init.c

@@ -91,8 +91,6 @@ int mt7925_mac_init(struct mt792x_dev *dev)
 
 	mt7925_mac_init_basic_rates(dev);
 
-	memzero_explicit(&dev->mt76.alpha2, sizeof(dev->mt76.alpha2));
-
 	return 0;
 }
 EXPORT_SYMBOL_GPL(mt7925_mac_init);

drivers/net/wireless/mediatek/mt76/mt7925/mac.c

@@ -6,6 +6,7 @@
 #include <linux/timekeeping.h>
 #include "mt7925.h"
 #include "../dma.h"
+#include "regd.h"
 #include "mac.h"
 #include "mcu.h"
 
@@ -1329,9 +1330,7 @@ void mt7925_mac_reset_work(struct work_struct *work)
 					    mt7925_vif_connect_iter, NULL);
 	mt76_connac_power_save_sched(&dev->mt76.phy, pm);
 
-	mt792x_mutex_acquire(dev);
-	mt7925_mcu_set_clc(dev, "00", ENVIRON_INDOOR);
-	mt792x_mutex_release(dev);
+	mt7925_regd_change(&dev->phy, "00");
 }
 
 void mt7925_coredump_work(struct work_struct *work)

drivers/net/wireless/mediatek/mt76/mt7925/main.c

@@ -1313,20 +1313,6 @@ void mt7925_mlo_pm_work(struct work_struct *work)
 					    mt7925_mlo_pm_iter, dev);
 }
 
-static bool is_valid_alpha2(const char *alpha2)
-{
-	if (!alpha2)
-		return false;
-
-	if (alpha2[0] == '0' && alpha2[1] == '0')
-		return true;
-
-	if (isalpha(alpha2[0]) && isalpha(alpha2[1]))
-		return true;
-
-	return false;
-}
-
 void mt7925_scan_work(struct work_struct *work)
 {
 	struct mt792x_phy *phy;
@@ -1335,7 +1321,6 @@ void mt7925_scan_work(struct work_struct *work)
 						scan_work.work);
 
 	while (true) {
-		struct mt76_dev *mdev = &phy->dev->mt76;
 		struct sk_buff *skb;
 		struct tlv *tlv;
 		int tlv_len;
@@ -1366,13 +1351,7 @@ void mt7925_scan_work(struct work_struct *work)
 			case UNI_EVENT_SCAN_DONE_CHNLINFO:
 				evt = (struct mt7925_mcu_scan_chinfo_event *)tlv->data;
 
-				if (!is_valid_alpha2(evt->alpha2))
-					break;
-
-				if (mdev->alpha2[0] != '0' && mdev->alpha2[1] != '0')
-					break;
-
-				mt7925_mcu_set_clc(phy->dev, evt->alpha2, ENVIRON_INDOOR);
+				mt7925_regd_change(phy, evt->alpha2);
 
 				break;
 			case UNI_EVENT_SCAN_DONE_NLO:

drivers/net/wireless/mediatek/mt76/mt7925/mcu.c

@@ -755,6 +755,7 @@ static int mt7925_load_clc(struct mt792x_dev *dev, const char *fw_name)
 		}
 	}
 
+	ret = mt7925_regd_init(phy);
 out:
 	release_firmware(fw);
 

drivers/net/wireless/mediatek/mt76/mt7925/regd.c

@@ -197,3 +197,64 @@ void mt7925_regd_notifier(struct wiphy *wiphy, struct regulatory_request *req)
 			       req->country_ie_env);
 	return;
 }
+
+static bool
+mt7925_regd_is_valid_alpha2(const char *alpha2)
+{
+	if (!alpha2)
+		return false;
+
+	if (alpha2[0] == '0' && alpha2[1] == '0')
+		return true;
+
+	if (isalpha(alpha2[0]) && isalpha(alpha2[1]))
+		return true;
+
+	return false;
+}
+
+int mt7925_regd_change(struct mt792x_phy *phy, char *alpha2)
+{
+	struct wiphy *wiphy = phy->mt76->hw->wiphy;
+	struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
+	struct mt792x_dev *dev = mt792x_hw_dev(hw);
+	struct mt76_dev *mdev = &dev->mt76;
+
+	if (dev->hw_full_reset)
+		return 0;
+
+	if (!mt7925_regd_is_valid_alpha2(alpha2) ||
+	    !mt7925_regd_clc_supported(dev))
+		return -EINVAL;
+
+	if (mdev->alpha2[0] != '0' && mdev->alpha2[1] != '0')
+		return 0;
+
+	/* do not need to update the same country twice */
+	if (!memcmp(alpha2, mdev->alpha2, 2))
+		return 0;
+
+	if (phy->chip_cap & MT792x_CHIP_CAP_11D_EN) {
+		return regulatory_hint(wiphy, alpha2);
+	} else {
+		return mt7925_mcu_set_clc(dev, alpha2, ENVIRON_INDOOR);
+	}
+}
+EXPORT_SYMBOL_GPL(mt7925_regd_change);
+
+int mt7925_regd_init(struct mt792x_phy *phy)
+{
+	struct wiphy *wiphy = phy->mt76->hw->wiphy;
+	struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
+	struct mt792x_dev *dev = mt792x_hw_dev(hw);
+	struct mt76_dev *mdev = &dev->mt76;
+
+	if (phy->chip_cap & MT792x_CHIP_CAP_11D_EN) {
+		wiphy->regulatory_flags |= REGULATORY_COUNTRY_IE_IGNORE |
+					   REGULATORY_DISABLE_BEACON_HINTS;
+	} else {
+		memzero_explicit(&mdev->alpha2, sizeof(mdev->alpha2));
+	}
+
+	return 0;
+}

drivers/net/wireless/mediatek/mt76/mt7925/regd.h

@@ -12,6 +12,8 @@ int mt7925_mcu_regd_update(struct mt792x_dev *dev, u8 *alpha2,
 void mt7925_regd_be_ctrl(struct mt792x_dev *dev, u8 *alpha2);
 void mt7925_regd_notifier(struct wiphy *wiphy, struct regulatory_request *req);
 bool mt7925_regd_clc_supported(struct mt792x_dev *dev);
+int mt7925_regd_change(struct mt792x_phy *phy, char *alpha2);
+int mt7925_regd_init(struct mt792x_phy *phy);
 
 #endif
 

drivers/net/wireless/mediatek/mt76/mt792x.h

@@ -28,6 +28,7 @@
 #define MT792x_CHIP_CAP_CLC_EVT_EN BIT(0)
 #define MT792x_CHIP_CAP_RSSI_NOTIFY_EVT_EN BIT(1)
 #define MT792x_CHIP_CAP_WF_RF_PIN_CTRL_EVT_EN BIT(3)
+#define MT792x_CHIP_CAP_11D_EN BIT(4)
 #define MT792x_CHIP_CAP_MLO_EN BIT(8)
 #define MT792x_CHIP_CAP_MLO_EML_EN BIT(9)