can: ifi: Fix TX DLC configuration

The TX DLC, the transmission length information, was not written
into the transmit configuration register. When using the CAN core
with different CAN controller, the receiving CAN controller will
receive only the ID part of the CAN frame, but no data at all.

This patch adds the TX DLC into the register to fix this issue.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Reviewed-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/ifi_canfd/ifi_canfd.c

@@ -749,8 +749,7 @@ static netdev_tx_t ifi_canfd_start_xmit(struct sk_buff *skb,
 {
 	struct ifi_canfd_priv *priv = netdev_priv(ndev);
 	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
-	u32 txst, txid;
-	u32 txdlc = 0;
+	u32 txst, txid, txdlc;
 	int i;
 
 	if (can_dropped_invalid_skb(ndev, skb))
@@ -773,13 +772,12 @@ static netdev_tx_t ifi_canfd_start_xmit(struct sk_buff *skb,
 		txid = cf->can_id & CAN_SFF_MASK;
 	}
 
-	if (priv->can.ctrlmode & (CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO)) {
-		if (can_is_canfd_skb(skb)) {
+	txdlc = can_len2dlc(cf->len);
+	if ((priv->can.ctrlmode & CAN_CTRLMODE_FD) && can_is_canfd_skb(skb)) {
 		txdlc |= IFI_CANFD_TXFIFO_DLC_EDL;
 		if (cf->flags & CANFD_BRS)
 			txdlc |= IFI_CANFD_TXFIFO_DLC_BRS;
 	}
-	}
 
 	if (cf->can_id & CAN_RTR_FLAG)
 		txdlc |= IFI_CANFD_TXFIFO_DLC_RTR;