PCI: designware: Make config accessor override checking symmetric

Drivers based on the DesignWare core can override the config read accessors
by supplying rd_own_conf() and rd_other_conf() function pointers.
dw_pcie_rd_conf() calls dw_pcie_rd_own_conf() (for accesses to the root
bus) or dw_pcie_rd_other_conf():

  dw_pcie_rd_conf
    dw_pcie_rd_own_conf                # if on root bus
    dw_pcie_rd_other_conf              # if not on root bus

Previously we checked for rd_other_conf() directly in dw_pcie_rd_conf(),
but we checked for rd_own_conf() in dw_pcie_rd_own_conf().

Check for rd_other_conf() in dw_pcie_rd_other_conf() to make this symmetric
with the rd_own_conf() checking, and similarly for the write path.

No functional change intended.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Pratyush Anand <pratyush.anand@gmail.com>

drivers/pci/host/pcie-designware.c

@@ -564,6 +564,9 @@ static int dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 	u64 cpu_addr;
 	void __iomem *va_cfg_base;
 
+	if (pp->ops->rd_other_conf)
+		return pp->ops->rd_other_conf(pp, bus, devfn, where, size, val);
+
 	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
 		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
 
@@ -598,6 +601,9 @@ static int dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
 	u64 cpu_addr;
 	void __iomem *va_cfg_base;
 
+	if (pp->ops->wr_other_conf)
+		return pp->ops->wr_other_conf(pp, bus, devfn, where, size, val);
+
 	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
 		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
 
@@ -660,9 +666,6 @@ static int dw_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
 	if (bus->number == pp->root_bus_nr)
 		return dw_pcie_rd_own_conf(pp, where, size, val);
 
-	if (pp->ops->rd_other_conf)
-		return pp->ops->rd_other_conf(pp, bus, devfn, where, size, val);
-
 	return dw_pcie_rd_other_conf(pp, bus, devfn, where, size, val);
 }
 
@@ -677,9 +680,6 @@ static int dw_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
 	if (bus->number == pp->root_bus_nr)
 		return dw_pcie_wr_own_conf(pp, where, size, val);
 
-	if (pp->ops->wr_other_conf)
-		return pp->ops->wr_other_conf(pp, bus, devfn, where, size, val);
-
 	return dw_pcie_wr_other_conf(pp, bus, devfn, where, size, val);
 }