r6040: save and restore MIER correctly in the interrupt routine

This patch saves the MIER register contents before treating
interrupts, then restores them correcty at the end of the
interrupt routine.

Signed-off-by: Joe Chou <Joe.Chou@rdc.com.tw>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/r6040.c b/drivers/net/r6040.c
index cc5e316de5719eb10570d7451ce2a2151ec7f1d0..990612328ca14f4b907b6e8f4ae6bd656624ec98 100644 (file)
--- a/drivers/net/r6040.c
+++ b/drivers/net/r6040.c
@@ -680,8 +680,10 @@ static irqreturn_t r6040_interrupt(int irq, void *dev_id)
        struct net_device *dev = dev_id;
        struct r6040_private *lp = netdev_priv(dev);
        void __iomem *ioaddr = lp->base;
-       u16 status;
+       u16 misr, status;
 
+       /* Save MIER */
+       misr = ioread16(ioaddr + MIER);
        /* Mask off RDC MAC interrupt */
        iowrite16(MSK_INT, ioaddr + MIER);
        /* Read MISR status and clear */
@@ -701,7 +703,7 @@ static irqreturn_t r6040_interrupt(int irq, void *dev_id)
                        dev->stats.rx_fifo_errors++;
 
                /* Mask off RX interrupt */
-               iowrite16(ioread16(ioaddr + MIER) & ~RX_INTS, ioaddr + MIER);
+               misr &= ~RX_INTS;
                netif_rx_schedule(dev, &lp->napi);
        }
 
@@ -709,6 +711,9 @@ static irqreturn_t r6040_interrupt(int irq, void *dev_id)
        if (status & TX_INTS)
                r6040_tx(dev);
 
+       /* Restore RDC MAC interrupt */
+       iowrite16(misr, ioaddr + MIER);
+
        return IRQ_HANDLED;
 }