pch_can: Divide poll function

To easy to read/understand, divide poll function into two sub-functions.
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/can/pch_can.c

@@ -819,72 +819,71 @@ static int pch_can_rx_normal(struct net_device *ndev, u32 int_stat)
 
 	return rcv_pkts;
 }
-static int pch_can_rx_poll(struct napi_struct *napi, int quota)
+
+static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
 {
-	struct net_device *ndev = napi->dev;
 	struct pch_can_priv *priv = netdev_priv(ndev);
 	struct net_device_stats *stats = &(priv->ndev->stats);
 	u32 dlc;
+
+	can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1);
+	iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
+		  &priv->regs->ifregs[1].cmask);
+	pch_can_check_if_busy(&priv->regs->ifregs[1].creq, int_stat);
+	dlc = get_can_dlc(ioread32(&priv->regs->ifregs[1].mcont) &
+			  PCH_IF_MCONT_DLC);
+	stats->tx_bytes += dlc;
+	stats->tx_packets++;
+	if (int_stat == PCH_TX_OBJ_END)
+		netif_wake_queue(ndev);
+}
+
+static int pch_can_rx_poll(struct napi_struct *napi, int quota)
+{
+	struct net_device *ndev = napi->dev;
+	struct pch_can_priv *priv = netdev_priv(ndev);
 	u32 int_stat;
 	int rcv_pkts = 0;
 	u32 reg_stat;
 
 	int_stat = pch_can_int_pending(priv);
 	if (!int_stat)
-		return 0;
+		goto end;
 
-INT_STAT:
-	if (int_stat == PCH_STATUS_INT) {
+	if ((int_stat == PCH_STATUS_INT) && (quota > 0)) {
 		reg_stat = ioread32(&priv->regs->stat);
 		if (reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) {
-			if ((reg_stat & PCH_LEC_ALL) != 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) {
-			iowrite32(PCH_CMASK_RX_TX_GET,
-				  &priv->regs->ifregs[1].cmask);
-			pch_can_check_if_busy(&priv->regs->ifregs[1].creq,
-					       ioread32(&priv->regs->intr));
+		if (reg_stat & PCH_TX_OK)
 			pch_can_bit_clear(&priv->regs->stat, PCH_TX_OK);
-		}
 
 		if (reg_stat & PCH_RX_OK)
 			pch_can_bit_clear(&priv->regs->stat, PCH_RX_OK);
 
 		int_stat = pch_can_int_pending(priv);
-		if (int_stat == PCH_STATUS_INT)
-			goto INT_STAT;
 	}
 
-MSG_OBJ:
+	if (quota == 0)
+		goto end;
+
 	if ((int_stat >= PCH_RX_OBJ_START) && (int_stat <= PCH_RX_OBJ_END)) {
-		rcv_pkts = pch_can_rx_normal(ndev, int_stat);
-		if (rcv_pkts < 0)
-			return 0;
+		rcv_pkts += pch_can_rx_normal(ndev, int_stat);
+		quota -= rcv_pkts;
+		if (quota < 0)
+			goto end;
 	} else if ((int_stat >= PCH_TX_OBJ_START) &&
 		   (int_stat <= PCH_TX_OBJ_END)) {
 		/* Handle transmission interrupt */
-		can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1);
-		iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
-			  &priv->regs->ifregs[1].cmask);
-		dlc = ioread32(&priv->regs->ifregs[1].mcont) &
-			       PCH_IF_MCONT_DLC;
-		pch_can_check_if_busy(&priv->regs->ifregs[1].creq, int_stat);
-		if (dlc > 8)
-			dlc = 8;
-		stats->tx_bytes += dlc;
-		stats->tx_packets++;
-		if (int_stat == PCH_TX_OBJ_END)
-			netif_wake_queue(ndev);
+		pch_can_tx_complete(ndev, int_stat);
 	}
 
-	int_stat = pch_can_int_pending(priv);
-	if (int_stat == PCH_STATUS_INT)
-		goto INT_STAT;
-	else if (int_stat >= 1 && int_stat <= 32)
-		goto MSG_OBJ;
-
+end:
 	napi_complete(napi);
 	pch_can_set_int_enables(priv, PCH_CAN_ALL);