scsi: megaraid_sas: enable intx only if msix request fails

Without this fix, driver will enable INTx Interrupt pin even though
MSI-x vectors are enabled. See below lspci output. DisINTx is unset for
MSIx setup.

lspci -s 85:00.0 -vvv |grep INT |grep Control
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
Stepping- SERR+ FastB2B- DisINTx-

After applying this fix, driver will enable INTx Interrupt pin only if
Legacy interrupt method is required.  See below lspci output. DisINTx is
set for MSIx setup.  lspci -s 85:00.0 -vvv |grep INT |grep Control
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
Stepping- SERR+ FastB2B- DisINTx+

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 7ac9a9e..016ffce 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -5034,10 +5034,12 @@ megasas_setup_irqs_msix(struct megasas_instance *instance, u8 is_probe)
                                         &instance->irq_context[j]);
                        /* Retry irq register for IO_APIC*/
                        instance->msix_vectors = 0;
-                       if (is_probe)
+                       if (is_probe) {
+                               pci_free_irq_vectors(instance->pdev);
                                return megasas_setup_irqs_ioapic(instance);
-                       else
+                       } else {
                                return -1;
+                       }
                }
        }
        return 0;
@@ -5277,9 +5279,11 @@ static int megasas_init_fw(struct megasas_instance *instance)
                        MPI2_REPLY_POST_HOST_INDEX_OFFSET);
        }
 
-       i = pci_alloc_irq_vectors(instance->pdev, 1, 1, PCI_IRQ_LEGACY);
-       if (i < 0)
-               goto fail_setup_irqs;
+       if (!instance->msix_vectors) {
+               i = pci_alloc_irq_vectors(instance->pdev, 1, 1, PCI_IRQ_LEGACY);
+               if (i < 0)
+                       goto fail_setup_irqs;
+       }
 
        dev_info(&instance->pdev->dev,
                "firmware supports msix\t: (%d)", fw_msix_count);