1 files changed, 39 insertions, 11 deletions

diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index 730ef3c384ca..02441fd57e9e 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -1763,24 +1763,50 @@ 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 */
         spin_lock_irqsave(&host->lock, flags);
 
         for (i = 0; i < host->n_ports; i++) {
-                struct ata_port *ap;
+                struct ata_port *ap = host->ports[i];
+                struct ata_queued_cmd *qc;
 
-                ap = host->ports[i];
-                if (ap &&
-                    !(ap->flags & ATA_FLAG_DISABLED)) {
-                        struct ata_queued_cmd *qc;
+                if (unlikely(ap->flags & ATA_FLAG_DISABLED))
+                        continue;
 
-                        qc = ata_qc_from_tag(ap, ap->link.active_tag);
-                        if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING)) &&
-                            (qc->flags & ATA_QCFLAG_ACTIVE))
+                qc = ata_qc_from_tag(ap, ap->link.active_tag);
+                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);
                 }
         }
 
@@ -3011,6 +3037,7 @@ EXPORT_SYMBOL_GPL(ata_pci_sff_activate_host);
  *      @ppi: array of port_info, must be enough for two ports
  *      @sht: scsi_host_template to use when registering the host
  *      @host_priv: host private_data
+ *      @hflag: host flags
  *
  *      This is a helper function which can be called from a driver's
  *      xxx_init_one() probe function if the hardware uses traditional
@@ -3031,8 +3058,8 @@ EXPORT_SYMBOL_GPL(ata_pci_sff_activate_host);
  *      Zero on success, negative on errno-based value on error.
  */
 int ata_pci_sff_init_one(struct pci_dev *pdev,
-                         const struct ata_port_info * const *ppi,
-                         struct scsi_host_template *sht, void *host_priv)
+                 const struct ata_port_info * const *ppi,
+                 struct scsi_host_template *sht, void *host_priv, int hflag)
 {
         struct device *dev = &pdev->dev;
         const struct ata_port_info *pi = NULL;
@@ -3067,6 +3094,7 @@ int ata_pci_sff_init_one(struct pci_dev *pdev,
         if (rc)
                 goto out;
         host->private_data = host_priv;
+        host->flags |= hflag;
 
         pci_set_master(pdev);
         rc = ata_pci_sff_activate_host(host, ata_sff_interrupt, sht);