mt76: introduce struct mt76_phy

This is preparation for supporting multiple wiphys per device to support the
concurrent dual-band feature of MT7615D

On the first wiphy, hw->priv will point to struct mt76_dev, which contains a
struct mt76_phy at the start. For the secondary wiphy, hw->priv will point
to a mt76_phy encapsulated in a driver specific struct

To simplify access to struct mt76_phy members from drivers, the driver specific
device struct is changed to add a union of struct mt76_dev and struct mt76_phy
as the first element
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -274,6 +274,7 @@ mt76_alloc_device(struct device *pdev, unsigned int size,
 		  const struct mt76_driver_ops *drv_ops)
 {
 	struct ieee80211_hw *hw;
+	struct mt76_phy *phy;
 	struct mt76_dev *dev;
 	int i;
 
@@ -286,6 +287,10 @@ mt76_alloc_device(struct device *pdev, unsigned int size,
 	dev->dev = pdev;
 	dev->drv = drv_ops;
 
+	phy = &dev->phy;
+	phy->dev = dev;
+	phy->hw = hw;
+
 	spin_lock_init(&dev->rx_lock);
 	spin_lock_init(&dev->lock);
 	spin_lock_init(&dev->cc_lock);

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

@@ -449,7 +449,14 @@ struct mt76_rx_status {
 	s8 chain_signal[IEEE80211_MAX_CHAINS];
 };
 
+struct mt76_phy {
+	struct ieee80211_hw *hw;
+	struct mt76_dev *dev;
+};
+
 struct mt76_dev {
+	struct mt76_phy phy; /* must be first */
+
 	struct ieee80211_hw *hw;
 	struct cfg80211_chan_def chandef;
 	struct ieee80211_channel *main_chan;
@@ -581,7 +588,7 @@ enum mt76_phy_type {
 #define __mt76_rmw_field(_dev, _reg, _field, _val)	\
 	__mt76_rmw(_dev, _reg, _field, FIELD_PREP(_field, _val))
 
-#define mt76_hw(dev) (dev)->mt76.hw
+#define mt76_hw(dev) (dev)->mphy.hw
 
 bool __mt76_poll(struct mt76_dev *dev, u32 offset, u32 mask, u32 val,
 		 int timeout);

drivers/net/wireless/mediatek/mt76/mt7603/mt7603.h

@@ -98,7 +98,10 @@ enum mt7603_reset_cause {
 };
 
 struct mt7603_dev {
-	struct mt76_dev mt76; /* must be first */
+	union { /* must be first */
+		struct mt76_dev mt76;
+		struct mt76_phy mphy;
+	};
 
 	const struct mt76_bus_ops *bus_ops;
 

drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h

@@ -80,7 +80,11 @@ struct mt7615_vif {
 };
 
 struct mt7615_dev {
-	struct mt76_dev mt76; /* must be first */
+	union { /* must be first */
+		struct mt76_dev mt76;
+		struct mt76_phy mphy;
+	};
+
 	u32 vif_mask;
 	u32 omac_mask;
 

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

@@ -70,7 +70,10 @@ struct mt76x02_beacon_ops {
 	(dev)->beacon_ops->pre_tbtt_enable(dev, enable)
 
 struct mt76x02_dev {
-	struct mt76_dev mt76; /* must be first */
+	union { /* must be first */
+		struct mt76_dev mt76;
+		struct mt76_phy mphy;
+	};
 
 	struct mac_address macaddr_list[8];