wifi: mt76: connac: fix stats->tx_bytes calculation

The stats->tx_bytes shall subtract retry byte from tx byte.

Fixes: 43eaa368 ("wifi: mt76: add PPDU based TxS support for WED device")
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/b3cd45596943cf5a06b2e08e2fe732ab0b51311b.1682285873.git.ryder.lee@mediatek.com

drivers/net/wireless/mediatek/mt76/mt76_connac2_mac.h

@@ -173,7 +173,7 @@ enum {
 #define MT_TXS5_MPDU_TX_CNT		GENMASK(31, 23)
 
 #define MT_TXS6_MPDU_FAIL_CNT		GENMASK(31, 23)
-
+#define MT_TXS7_MPDU_RETRY_BYTE		GENMASK(22, 0)
 #define MT_TXS7_MPDU_RETRY_CNT		GENMASK(31, 23)
 
 /* RXD DW0 */

drivers/net/wireless/mediatek/mt76/mt76_connac_mac.c

@@ -608,7 +608,8 @@ bool mt76_connac2_mac_fill_txs(struct mt76_dev *dev, struct mt76_wcid *wcid,
 	/* PPDU based reporting */
 	if (FIELD_GET(MT_TXS0_TXS_FORMAT, txs) > 1) {
 		stats->tx_bytes +=
-			le32_get_bits(txs_data[5], MT_TXS5_MPDU_TX_BYTE);
+			le32_get_bits(txs_data[5], MT_TXS5_MPDU_TX_BYTE) -
+			le32_get_bits(txs_data[7], MT_TXS7_MPDU_RETRY_BYTE);
 		stats->tx_packets +=
 			le32_get_bits(txs_data[5], MT_TXS5_MPDU_TX_CNT);
 		stats->tx_failed +=