pch_can: Optimize "if" condition in rx/tx processing

For reduce "if" condition, easy to read/understand the code,
optimize "if" condition in rx/tx processing.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/can/pch_can.c

@@ -746,19 +746,16 @@ static int pch_can_poll(struct napi_struct *napi, int quota)
 
 	if (int_stat == PCH_STATUS_INT) {
 		reg_stat = ioread32(&priv->regs->stat);
-		if (reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) {
-			if (reg_stat & PCH_BUS_OFF ||
-			   (reg_stat & PCH_LEC_ALL) != PCH_LEC_ALL) {
-				pch_can_error(ndev, reg_stat);
-				quota--;
-			}
-		}
 
-		if (reg_stat & PCH_TX_OK)
-			pch_can_bit_clear(&priv->regs->stat, PCH_TX_OK);
+		if ((reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) &&
+		   ((reg_stat & PCH_LEC_ALL) != PCH_LEC_ALL)) {
+			pch_can_error(ndev, reg_stat);
+			quota--;
+		}
 
-		if (reg_stat & PCH_RX_OK)
-			pch_can_bit_clear(&priv->regs->stat, PCH_RX_OK);
+		if (reg_stat & (PCH_TX_OK | PCH_RX_OK))
+			pch_can_bit_clear(&priv->regs->stat,
+					  reg_stat & (PCH_TX_OK | PCH_RX_OK));
 
 		int_stat = pch_can_int_pending(priv);
 	}
@@ -900,14 +897,13 @@ static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
 	if (can_dropped_invalid_skb(ndev, skb))
 		return NETDEV_TX_OK;
 
+	tx_obj_no = priv->tx_obj;
 	if (priv->tx_obj == PCH_TX_OBJ_END) {
 		if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK)
 			netif_stop_queue(ndev);
 
-		tx_obj_no = priv->tx_obj;
 		priv->tx_obj = PCH_TX_OBJ_START;
 	} else {
-		tx_obj_no = priv->tx_obj;
 		priv->tx_obj++;
 	}
 
@@ -926,9 +922,7 @@ static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
 	id2 |= PCH_ID_MSGVAL;
 
 	/* If remote frame has to be transmitted.. */
-	if (cf->can_id & CAN_RTR_FLAG)
-		id2 &= ~PCH_ID2_DIR;
-	else
+	if (!(cf->can_id & CAN_RTR_FLAG))
 		id2 |= PCH_ID2_DIR;
 
 	iowrite32(id2, &priv->regs->ifregs[1].id2);