[SCSI] qla2xxx: Add MSI support.

Supported ISP types include ISP2422 and revision-2 type
ISP2432 chips.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index d488561..ca46346 100644
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -1726,6 +1726,17 @@
 	qla_printk(KERN_WARNING, ha,
 	    "MSI-X: Falling back-to INTa mode -- %d.\n", ret);
 skip_msix:
+
+	if (!IS_QLA24XX(ha))
+		goto skip_msi;
+
+	ret = pci_enable_msi(ha->pdev);
+	if (!ret) {
+		DEBUG2(qla_printk(KERN_INFO, ha, "MSI: Enabled.\n"));
+		ha->flags.msi_enabled = 1;
+	}
+skip_msi:
+
 	ret = request_irq(ha->pdev->irq, ha->isp_ops.intr_handler,
 	    IRQF_DISABLED|IRQF_SHARED, QLA2XXX_DRIVER_NAME, ha);
 	if (!ret) {
@@ -1746,6 +1757,8 @@
 
 	if (ha->flags.msix_enabled)
 		qla24xx_disable_msix(ha);
-	else if (ha->flags.inta_enabled)
+	else if (ha->flags.inta_enabled) {
 		free_irq(ha->host->irq, ha);
+		pci_disable_msi(ha->pdev);
+	}
 }