PCI: tegra: Use generic accessors where possible

The Tegra PCI host controller can generate configuration space accesses
with byte, word and dword granularity for devices. Only root ports can't
have their configuration space accessed in this way.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/host/pci-tegra.c

@@ -491,12 +491,32 @@ static void __iomem *tegra_pcie_map_bus(struct pci_bus *bus,
 	return addr;
 }
 
+static int tegra_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
+				  int where, int size, u32 *value)
+{
+	if (bus->number == 0)
+		return pci_generic_config_read32(bus, devfn, where, size,
+						 value);
+
+	return pci_generic_config_read(bus, devfn, where, size, value);
+}
+
+static int tegra_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
+				   int where, int size, u32 value)
+{
+	if (bus->number == 0)
+		return pci_generic_config_write32(bus, devfn, where, size,
+						  value);
+
+	return pci_generic_config_write(bus, devfn, where, size, value);
+}
+
 static struct pci_ops tegra_pcie_ops = {
 	.add_bus = tegra_pcie_add_bus,
 	.remove_bus = tegra_pcie_remove_bus,
 	.map_bus = tegra_pcie_map_bus,
-	.read = pci_generic_config_read32,
-	.write = pci_generic_config_write32,
+	.read = tegra_pcie_config_read,
+	.write = tegra_pcie_config_write,
 };
 
 static unsigned long tegra_pcie_port_get_pex_ctrl(struct tegra_pcie_port *port)