sata_mv: disregard masked irqs

Part four of simplifying/fixing handling of the main_irq_mask register
to resolve unexpected interrupt issues observed in 2.6.26-rc*.

Ignore masked IRQs in mv_interrupt().
This prevents "unexpected device interrupt while idle" messages.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index 47dae7a..eb7f3da 100644 (file)
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -2200,20 +2200,21 @@ static irqreturn_t mv_interrupt(int irq, void *dev_instance)
        struct ata_host *host = dev_instance;
        struct mv_host_priv *hpriv = host->private_data;
        unsigned int handled = 0;
-       u32 main_irq_cause, main_irq_mask;
+       u32 main_irq_cause, main_irq_mask, pending_irqs;
 
        spin_lock(&host->lock);
        main_irq_cause = readl(hpriv->main_irq_cause_addr);
        main_irq_mask  = readl(hpriv->main_irq_mask_addr);
+       pending_irqs   = main_irq_cause & main_irq_mask;
        /*
         * Deal with cases where we either have nothing pending, or have read
         * a bogus register value which can indicate HW removal or PCI fault.
         */
-       if ((main_irq_cause & main_irq_mask) && (main_irq_cause != 0xffffffffU)) {
-               if (unlikely((main_irq_cause & PCI_ERR) && HAS_PCI(host)))
+       if (pending_irqs && main_irq_cause != 0xffffffffU) {
+               if (unlikely((pending_irqs & PCI_ERR) && HAS_PCI(host)))
                        handled = mv_pci_error(host, hpriv->base);
                else
-                       handled = mv_host_intr(host, main_irq_cause);
+                       handled = mv_host_intr(host, pending_irqs);
        }
        spin_unlock(&host->lock);
        return IRQ_RETVAL(handled);