3 files changed, 48 insertions, 8 deletions

diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c
index b5f614b9c245..c33806654e46 100644
--- a/drivers/ata/ata_piix.c
+++ b/drivers/ata/ata_piix.c
@@ -173,6 +173,7 @@ static int piix_sidpr_scr_read(struct ata_link *link,
                                unsigned int reg, u32 *val);
 static int piix_sidpr_scr_write(struct ata_link *link,
                                 unsigned int reg, u32 val);
+static bool piix_irq_check(struct ata_port *ap);
 #ifdef CONFIG_PM
 static int piix_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg);
 static int piix_pci_device_resume(struct pci_dev *pdev);
@@ -317,8 +318,13 @@ static struct scsi_host_template piix_sht = {
         ATA_BMDMA_SHT(DRV_NAME),
 };
 
-static struct ata_port_operations piix_pata_ops = {
+static struct ata_port_operations piix_sata_ops = {
         .inherits               = &ata_bmdma32_port_ops,
+        .sff_irq_check          = piix_irq_check,
+};
+
+static struct ata_port_operations piix_pata_ops = {
+        .inherits               = &piix_sata_ops,
         .cable_detect           = ata_cable_40wire,
         .set_piomode            = piix_set_piomode,
         .set_dmamode            = piix_set_dmamode,
@@ -336,10 +342,6 @@ static struct ata_port_operations ich_pata_ops = {
         .set_dmamode            = ich_set_dmamode,
 };
 
-static struct ata_port_operations piix_sata_ops = {
-        .inherits               = &ata_bmdma32_port_ops,
-};
-
 static struct ata_port_operations piix_sidpr_sata_ops = {
         .inherits               = &piix_sata_ops,
         .hardreset              = sata_std_hardreset,
@@ -970,6 +972,14 @@ static int piix_sidpr_scr_write(struct ata_link *link,
         return 0;
 }
 
+static bool piix_irq_check(struct ata_port *ap)
+{
+        if (unlikely(!ap->ioaddr.bmdma_addr))
+                return false;
+
+        return ap->ops->bmdma_status(ap) & ATA_DMA_INTR;
+}
+
 #ifdef CONFIG_PM
 static int piix_broken_suspend(void)
 {
diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index c62ed13b0596..c2661ea70330 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -1763,7 +1763,7 @@ irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
 {
         struct ata_host *host = dev_instance;
         unsigned int i;
-        unsigned int handled = 0;
+        unsigned int handled = 0, polling = 0;
         unsigned long flags;
 
         /* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
@@ -1777,8 +1777,37 @@ irqreturn_t ata_sff_interrupt(int irq, void *dev_instance)
                         continue;
 
                 qc = ata_qc_from_tag(ap, ap->link.active_tag);
-                if (qc && !(qc->tf.flags & ATA_TFLAG_POLLING))
-                        handled |= ata_sff_host_intr(ap, qc);
+                if (qc) {
+                        if (!(qc->tf.flags & ATA_TFLAG_POLLING))
+                                handled |= ata_sff_host_intr(ap, qc);
+                        else
+                                polling |= 1 << i;
+                }
+        }
+
+        /*
+         * If no port was expecting IRQ but the controller is actually
+         * asserting IRQ line, nobody cared will ensue.  Check IRQ
+         * pending status if available and clear spurious IRQ.
+         */
+        if (!handled) {
+                for (i = 0; i < host->n_ports; i++) {
+                        struct ata_port *ap = host->ports[i];
+
+                        if (polling & (1 << i))
+                                continue;
+
+                        if (!ap->ops->sff_irq_check ||
+                            !ap->ops->sff_irq_check(ap))
+                                continue;
+
+                        if (printk_ratelimit())
+                                ata_port_printk(ap, KERN_INFO,
+                                                "clearing spurious IRQ\n");
+
+                        ap->ops->sff_check_status(ap);
+                        ap->ops->sff_irq_clear(ap);
+                }
         }
 
         spin_unlock_irqrestore(&host->lock, flags);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 73112250862c..5fb888462359 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -857,6 +857,7 @@ struct ata_port_operations {
         unsigned int (*sff_data_xfer)(struct ata_device *dev,
                         unsigned char *buf, unsigned int buflen, int rw);
         u8   (*sff_irq_on)(struct ata_port *);
+        bool (*sff_irq_check)(struct ata_port *);
         void (*sff_irq_clear)(struct ata_port *);
 
         void (*bmdma_setup)(struct ata_queued_cmd *qc);