mt76: move mt76x02_insert_hdr_pad in mt76-core module

Move mt76x02_insert_hdr_pad in m76-core and rename it in
mt76_insert_hdr_pad in order to be used in mt76_dma_tx_queue_skb.
This is a preliminary patch in order to properly support tx dma
mapping for new chipsets (e.g. mt7615)

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

mt76.h

@@ -656,6 +656,20 @@ int mt76_dma_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid,
 			  struct sk_buff *skb, struct mt76_wcid *wcid,
 			  struct ieee80211_sta *sta);
 
+static inline void mt76_insert_hdr_pad(struct sk_buff *skb)
+{
+	int len = ieee80211_get_hdrlen_from_skb(skb);
+
+	if (len % 4 == 0)
+		return;
+
+	skb_push(skb, 2);
+	memmove(skb->data, skb->data + 2, len);
+
+	skb->data[len] = 0;
+	skb->data[len + 1] = 0;
+}
+
 void mt76_rx(struct mt76_dev *dev, enum mt76_rxq_id q, struct sk_buff *skb);
 void mt76_tx(struct mt76_dev *dev, struct ieee80211_sta *sta,
 	     struct mt76_wcid *wcid, struct sk_buff *skb);

mt76x02.h

@@ -164,7 +164,6 @@ void mt76x02_set_tx_ackto(struct mt76x02_dev *dev);
 void mt76x02_set_coverage_class(struct ieee80211_hw *hw,
 				s16 coverage_class);
 int mt76x02_set_rts_threshold(struct ieee80211_hw *hw, u32 val);
-int mt76x02_insert_hdr_pad(struct sk_buff *skb);
 void mt76x02_remove_hdr_pad(struct sk_buff *skb, int len);
 bool mt76x02_tx_status_data(struct mt76_dev *mdev, u8 *update);
 void mt76x02_queue_rx_skb(struct mt76_dev *mdev, enum mt76_rxq_id q,

mt76x02_txrx.c

@@ -155,7 +155,6 @@ int mt76x02_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
 	struct mt76x02_txwi *txwi = txwi_ptr;
 	int qsel = MT_QSEL_EDCA;
 	int pid;
-	int ret;
 
 	if (qid == MT_TXQ_PSD && wcid && wcid->idx < 128)
 		mt76x02_mac_wcid_set_drop(dev, wcid->idx, false);
@@ -165,9 +164,7 @@ int mt76x02_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
 	pid = mt76_tx_status_skb_add(mdev, wcid, skb);
 	txwi->pktid = pid;
 
-	ret = mt76x02_insert_hdr_pad(skb);
-	if (ret < 0)
-		return ret;
+	mt76_insert_hdr_pad(skb);
 
 	if (pid >= MT_PACKET_ID_FIRST)
 		qsel = MT_QSEL_MGMT;

mt76x02_usb_core.c

@@ -82,7 +82,7 @@ int mt76x02u_tx_prepare_skb(struct mt76_dev *mdev, void *data,
 	enum mt76_qsel qsel;
 	u32 flags;
 
-	mt76x02_insert_hdr_pad(skb);
+	mt76_insert_hdr_pad(skb);
 
 	txwi = (struct mt76x02_txwi *)(skb->data - sizeof(struct mt76x02_txwi));
 	mt76x02_mac_write_txwi(dev, txwi, skb, wcid, sta, len);

mt76x02_util.c

@@ -566,22 +566,6 @@ void mt76x02_sta_rate_tbl_update(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL_GPL(mt76x02_sta_rate_tbl_update);
 
-int mt76x02_insert_hdr_pad(struct sk_buff *skb)
-{
-	int len = ieee80211_get_hdrlen_from_skb(skb);
-
-	if (len % 4 == 0)
-		return 0;
-
-	skb_push(skb, 2);
-	memmove(skb->data, skb->data + 2, len);
-
-	skb->data[len] = 0;
-	skb->data[len + 1] = 0;
-	return 2;
-}
-EXPORT_SYMBOL_GPL(mt76x02_insert_hdr_pad);
-
 void mt76x02_remove_hdr_pad(struct sk_buff *skb, int len)
 {
 	int hdrlen;