[libata] sata_mv: Tighten up interrupt masking in mv_qc_issue()

so that it doesn't miss any protocols.  Handle future cases where a
qc is specially marked for polled issue or where a particular chip
version prefers interrupts over polling for PIO.

This mimics the polling decision logic from ata_sff_qc_issue().
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/sata_mv.c

@@ -1809,7 +1809,7 @@ static unsigned int mv_qc_issue(struct ata_queued_cmd *qc)
 	void __iomem *port_mmio = mv_ap_base(ap);
 	struct mv_port_priv *pp = ap->private_data;
 	u32 in_index;
-	unsigned int port_irqs = DONE_IRQ | ERR_IRQ;
+	unsigned int port_irqs;
 
 	switch (qc->tf.protocol) {
 	case ATA_PROT_DMA:
@@ -1842,10 +1842,19 @@ static unsigned int mv_qc_issue(struct ata_queued_cmd *qc)
 					"this may fail due to h/w errata\n");
 		}
 		/* drop through */
+	case ATA_PROT_NODATA:
 	case ATAPI_PROT_PIO:
-		port_irqs = ERR_IRQ;	/* leave DONE_IRQ masked for PIO */
-		/* drop through */
-	default:
+	case ATAPI_PROT_NODATA:
+		if (ap->flags & ATA_FLAG_PIO_POLLING)
+			qc->tf.flags |= ATA_TFLAG_POLLING;
+		break;
+	}
+
+	if (qc->tf.flags & ATA_TFLAG_POLLING)
+		port_irqs = ERR_IRQ;	/* mask device interrupt when polling */
+	else
+		port_irqs = ERR_IRQ | DONE_IRQ;	/* unmask all interrupts */
+
 	/*
 	 * We're about to send a non-EDMA capable command to the
 	 * port.  Turn off EDMA so there won't be problems accessing
@@ -1855,7 +1864,6 @@ static unsigned int mv_qc_issue(struct ata_queued_cmd *qc)
 	mv_clear_and_enable_port_irqs(ap, mv_ap_base(ap), port_irqs);
 	mv_pmp_select(ap, qc->dev->link->pmp);
 	return ata_sff_qc_issue(qc);
-	}
 }
 
 static struct ata_queued_cmd *mv_get_active_qc(struct ata_port *ap)