PCI: j721e: Fix host/endpoint dependencies

The j721e driver has a single platform driver that can be built-in or a
loadable module, but it calls two separate backend drivers depending on
whether it is a host or endpoint.

If the two modes are not the same, we can end up with a situation where the
built-in pci-j721e driver tries to call the modular host or endpoint
driver, which causes a link failure:

  ld.lld-21: error: undefined symbol: cdns_pcie_ep_setup
  >>> referenced by pci-j721e.c
  >>>               drivers/pci/controller/cadence/pci-j721e.o:(j721e_pcie_probe) in archive vmlinux.a

  ld.lld-21: error: undefined symbol: cdns_pcie_host_setup
  >>> referenced by pci-j721e.c
  >>>               drivers/pci/controller/cadence/pci-j721e.o:(j721e_pcie_probe) in archive vmlinux.a

Rework the dependencies so that the 'select' is done by the common Kconfig
symbol, based on which of the two are enabled. Effectively this means that
having one built-in makes the other either built-in or disabled, but all
configurations will now build.

Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Manivannan Sadhasivam <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Siddharth Vadapalli <[email protected]>
Link: https://patch.msgid.link/[email protected]

Author: arndb

drivers/pci/controller/cadence/Kconfig

@@ -44,12 +44,13 @@ config PCIE_CADENCE_PLAT_EP
 
 config PCI_J721E
 	tristate
+	select PCIE_CADENCE_HOST if PCI_J721E_HOST != n
+	select PCIE_CADENCE_EP if PCI_J721E_EP != n
 
 config PCI_J721E_HOST
 	tristate "TI J721E PCIe controller (host mode)"
 	depends on ARCH_K3 || COMPILE_TEST
 	depends on OF
-	select PCIE_CADENCE_HOST
 	select PCI_J721E
 	help
 	  Say Y here if you want to support the TI J721E PCIe platform
@@ -61,7 +62,6 @@ config PCI_J721E_EP
 	depends on ARCH_K3 || COMPILE_TEST
 	depends on OF
 	depends on PCI_ENDPOINT
-	select PCIE_CADENCE_EP
 	select PCI_J721E
 	help
 	  Say Y here if you want to support the TI J721E PCIe platform

drivers/pci/controller/cadence/pci-j721e.c

@@ -475,7 +475,7 @@ static int j721e_pcie_probe(struct platform_device *pdev)
 
 	switch (mode) {
 	case PCI_MODE_RC:
-		if (!IS_ENABLED(CONFIG_PCIE_CADENCE_HOST))
+		if (!IS_ENABLED(CONFIG_PCI_J721E_HOST))
 			return -ENODEV;
 
 		bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
@@ -494,7 +494,7 @@ static int j721e_pcie_probe(struct platform_device *pdev)
 		pcie->cdns_pcie = cdns_pcie;
 		break;
 	case PCI_MODE_EP:
-		if (!IS_ENABLED(CONFIG_PCIE_CADENCE_EP))
+		if (!IS_ENABLED(CONFIG_PCI_J721E_EP))
 			return -ENODEV;
 
 		ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);