[PATCH] PCI: altera: Allow building as module

[Ley Foon Tan <ley.foon.tan@intel.com>]

Altera PCIe Rootport IP is a soft IP and is only available after
FPGA image is programmed.

Make driver modulable to support use case FPGA image is programmed
after kernel is booted. User proram FPGA image in kernel then only load
PCIe driver module.

Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
---
 drivers/pci/controller/Kconfig       |  2 +-
 drivers/pci/controller/pcie-altera.c | 28 ++++++++++++++++++++++++++--
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 6012f3059acd..4b550f9cdd56 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -174,7 +174,7 @@ config PCIE_IPROC_MSI
 	  PCIe controller
 
 config PCIE_ALTERA
-	bool "Altera PCIe controller"
+	tristate "Altera PCIe controller"
 	depends on ARM || NIOS2 || ARM64 || COMPILE_TEST
 	help
 	  Say Y here if you want to enable PCIe controller support on Altera
diff --git a/drivers/pci/controller/pcie-altera.c b/drivers/pci/controller/pcie-altera.c
index 27edcebd1726..6c86bc69ace8 100644
--- a/drivers/pci/controller/pcie-altera.c
+++ b/drivers/pci/controller/pcie-altera.c
@@ -10,6 +10,7 @@
 #include <linux/interrupt.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/init.h>
+#include <linux/module.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
 #include <linux/of_irq.h>
@@ -705,6 +706,13 @@ static int altera_pcie_init_irq_domain(struct altera_pcie *pcie)
 	return 0;
 }
 
+static int altera_pcie_irq_teardown(struct altera_pcie *pcie)
+{
+	irq_set_chained_handler_and_data(pcie->irq, NULL, NULL);
+	irq_domain_remove(pcie->irq_domain);
+	irq_dispose_mapping(pcie->irq);
+}
+
 static int altera_pcie_parse_dt(struct altera_pcie *pcie)
 {
 	struct device *dev = &pcie->pdev->dev;
@@ -798,6 +806,7 @@ static int altera_pcie_probe(struct platform_device *pdev)
 
 	pcie = pci_host_bridge_priv(bridge);
 	pcie->pdev = pdev;
+	platform_set_drvdata(pdev, pcie);
 
 	match = of_match_device(altera_pcie_of_match, &pdev->dev);
 	if (!match)
@@ -855,13 +864,28 @@ static int altera_pcie_probe(struct platform_device *pdev)
 	return ret;
 }
 
+static int altera_pcie_remove(struct platform_device *pdev)
+{
+	struct altera_pcie *pcie = platform_get_drvdata(pdev);
+	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
+
+	pci_stop_root_bus(bridge->bus);
+	pci_remove_root_bus(bridge->bus);
+	pci_free_resource_list(&pcie->resources);
+	altera_pcie_irq_teardown(pcie);
+
+	return 0;
+}
+
 static struct platform_driver altera_pcie_driver = {
 	.probe		= altera_pcie_probe,
+	.remove		= altera_pcie_remove,
 	.driver = {
 		.name	= "altera-pcie",
 		.of_match_table = altera_pcie_of_match,
-		.suppress_bind_attrs = true,
 	},
 };
 
-builtin_platform_driver(altera_pcie_driver);
+MODULE_DEVICE_TABLE(of, altera_pcie_of_match);
+module_platform_driver(altera_pcie_driver);
+MODULE_LICENSE("GPL v2");
-- 
2.19.0