mt76: mt76u: introduce mt76u_skb_dma_info routine

Introduce mt76u_skb_dma_info utility routine in mt76-usb module in order
to be reused adding mt7663u support
Co-developed-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -881,6 +881,7 @@ mt76u_bulk_msg(struct mt76_dev *dev, void *data, int len, int *actual_len,
 	return usb_bulk_msg(udev, pipe, data, len, actual_len, timeout);
 }
 
+int mt76u_skb_dma_info(struct sk_buff *skb, u32 info);
 int mt76u_vendor_request(struct mt76_dev *dev, u8 req,
 			 u8 req_type, u16 val, u16 offset,
 			 void *buf, size_t len);

drivers/net/wireless/mediatek/mt76/mt76x02_usb_core.c

@@ -46,8 +46,7 @@ EXPORT_SYMBOL_GPL(mt76x02u_mac_start);
 
 int mt76x02u_skb_dma_info(struct sk_buff *skb, int port, u32 flags)
 {
-	struct sk_buff *iter, *last = skb;
-	u32 info, pad;
+	u32 info;
 
 	/* Buffer layout:
 	 *	|   4B   | xfer len |      pad       |  4B  |
@@ -57,28 +56,8 @@ int mt76x02u_skb_dma_info(struct sk_buff *skb, int port, u32 flags)
 	 */
 	info = FIELD_PREP(MT_TXD_INFO_LEN, round_up(skb->len, 4)) |
 	       FIELD_PREP(MT_TXD_INFO_DPORT, port) | flags;
-	put_unaligned_le32(info, skb_push(skb, sizeof(info)));
 
-	/* Add zero pad of 4 - 7 bytes */
-	pad = round_up(skb->len, 4) + 4 - skb->len;
-
-	/* First packet of a A-MSDU burst keeps track of the whole burst
-	 * length, need to update length of it and the last packet.
-	 */
-	skb_walk_frags(skb, iter) {
-		last = iter;
-		if (!iter->next) {
-			skb->data_len += pad;
-			skb->len += pad;
-			break;
-		}
-	}
-
-	if (skb_pad(last, pad))
-		return -ENOMEM;
-	__skb_put(last, pad);
-
-	return 0;
+	return mt76u_skb_dma_info(skb, info);
 }
 
 int mt76x02u_tx_prepare_skb(struct mt76_dev *mdev, void *data,

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

@@ -907,6 +907,35 @@ mt76u_tx_setup_buffers(struct mt76_dev *dev, struct sk_buff *skb,
 	return urb->num_sgs;
 }
 
+int mt76u_skb_dma_info(struct sk_buff *skb, u32 info)
+{
+	struct sk_buff *iter, *last = skb;
+	u32 pad;
+
+	put_unaligned_le32(info, skb_push(skb, sizeof(info)));
+	/* Add zero pad of 4 - 7 bytes */
+	pad = round_up(skb->len, 4) + 4 - skb->len;
+
+	/* First packet of a A-MSDU burst keeps track of the whole burst
+	 * length, need to update length of it and the last packet.
+	 */
+	skb_walk_frags(skb, iter) {
+		last = iter;
+		if (!iter->next) {
+			skb->data_len += pad;
+			skb->len += pad;
+			break;
+		}
+	}
+
+	if (skb_pad(last, pad))
+		return -ENOMEM;
+	__skb_put(last, pad);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mt76u_skb_dma_info);
+
 static int
 mt76u_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid,
 		   struct sk_buff *skb, struct mt76_wcid *wcid,