scsi: arcmsr: Add driver module parameter msi_enable

Add module parameter msi_enable so user has the option of disabling MSI
interrupts if there is a platform problem.

Signed-off-by: Ching Huang <ching2048@areca.com.tw>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index 52f8e1cfd10c606d4f2ceeaf83eaa01420fbb9b2..367904fb7cdffc9e8d88a78c5cafa9fafd5a0ada 100644 (file)
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -75,6 +75,10 @@ MODULE_DESCRIPTION("Areca ARC11xx/12xx/16xx/188x SAS/SATA RAID Controller Driver
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_VERSION(ARCMSR_DRIVER_VERSION);
 
+static int msi_enable = 1;
+module_param(msi_enable, int, S_IRUGO);
+MODULE_PARM_DESC(msi_enable, "Enable MSI interrupt(0 ~ 1), msi_enable=1(enable), =0(disable)");
+
 static int host_can_queue = ARCMSR_DEFAULT_OUTSTANDING_CMD;
 module_param(host_can_queue, int, S_IRUGO);
 MODULE_PARM_DESC(host_can_queue, " adapter queue depth(32 ~ 1024), default is 128");
@@ -831,11 +835,17 @@ arcmsr_request_irq(struct pci_dev *pdev, struct AdapterControlBlock *acb)
                pr_info("arcmsr%d: msi-x enabled\n", acb->host->host_no);
                flags = 0;
        } else {
-               nvec = pci_alloc_irq_vectors(pdev, 1, 1,
-                               PCI_IRQ_MSI | PCI_IRQ_LEGACY);
+               if (msi_enable == 1) {
+                       nvec = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
+                       if (nvec == 1) {
+                               dev_info(&pdev->dev, "msi enabled\n");
+                               goto msi_int1;
+                       }
+               }
+               nvec = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_LEGACY);
                if (nvec < 1)
                        return FAILED;
-
+msi_int1:
                flags = IRQF_SHARED;
        }