PCI: Use dev->irq instead of dev->pin to enable non MSI/INTx interrupt

On some platforms, root port has neither MSI/MSI-X nor INTx interrupt
generated in RC mode. In this case, we have to use other interrupt, e.g.,
system shared interrupt, for port service IRQ to have AER, Hot-plug, etc.,
services work.

Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index 75915b30ad19..eaa39fb448c4 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -200,10 +200,13 @@ static int init_service_irqs(struct pci_dev *dev, int *irqs, int mask)
 {
         int i, irq = -1;
 
-        /* We have to use INTx if MSI cannot be used for PCIe PME or pciehp. */
+        /*
+         * If MSI cannot be used for PCIe PME or hotplug, we have to use
+         * INTx or other interrupts, e.g. system shared interrupt.
+         */
         if (((mask & PCIE_PORT_SERVICE_PME) && pcie_pme_no_msi()) ||
             ((mask & PCIE_PORT_SERVICE_HP) && pciehp_no_msi())) {
-                if (dev->pin)
+                if (dev->irq)
                         irq = dev->irq;
                 goto no_msi;
         }
@@ -212,8 +215,12 @@ static int init_service_irqs(struct pci_dev *dev, int *irqs, int mask)
         if (!pcie_port_enable_msix(dev, irqs, mask))
                 return 0;
 
-        /* We're not going to use MSI-X, so try MSI and fall back to INTx */
-        if (!pci_enable_msi(dev) || dev->pin)
+        /*
+         * We're not going to use MSI-X, so try MSI and fall back to INTx.
+         * If neither MSI/MSI-X nor INTx available, try other interrupt.  On
+         * some platforms, root port doesn't support MSI/MSI-X/INTx in RC mode.
+         */
+        if (!pci_enable_msi(dev) || dev->irq)
                 irq = dev->irq;
 
  no_msi: