[PATCH v8 9/9] PCI: mediatek: Add loadable kernel module support

[honghui.zhang]

From: Honghui Zhang <honghui.zh...@mediatek.com>

Implement remove callback function for Mediatek PCIe driver to add
loadable kernel module support.

Signed-off-by: Honghui Zhang <honghui.zh...@mediatek.com>
Reviewed-by: Ryder Lee <ryder....@mediatek.com>
---
 drivers/pci/controller/Kconfig         |  2 +-
 drivers/pci/controller/pcie-mediatek.c | 51 +++++++++++++++++++++++++++++++++-
 2 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 028b287..465790f 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -231,7 +231,7 @@ config PCIE_ROCKCHIP_EP
          available to support GEN2 with 4 slots.
 
 config PCIE_MEDIATEK
-       bool "MediaTek PCIe controller"
+       tristate "MediaTek PCIe controller"
        depends on ARCH_MEDIATEK || COMPILE_TEST
        depends on OF
        depends on PCI_MSI_IRQ_DOMAIN
diff --git a/drivers/pci/controller/pcie-mediatek.c 
b/drivers/pci/controller/pcie-mediatek.c
index daba78f..5048adb 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -15,6 +15,7 @@
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/msi.h>
+#include <linux/module.h>
 #include <linux/of_address.h>
 #include <linux/of_pci.h>
 #include <linux/of_platform.h>
@@ -532,6 +533,27 @@ static void mtk_pcie_enable_msi(struct mtk_pcie_port *port)
        writel(val, port->base + PCIE_INT_MASK);
 }
 
+static void mtk_pcie_irq_teardown(struct mtk_pcie *pcie)
+{
+       struct mtk_pcie_port *port, *tmp;
+
+       list_for_each_entry_safe(port, tmp, &pcie->ports, list) {
+               irq_set_chained_handler_and_data(port->irq, NULL, NULL);
+
+               if (port->irq_domain)
+                       irq_domain_remove(port->irq_domain);
+
+               if (IS_ENABLED(CONFIG_PCI_MSI)) {
+                       if (port->msi_domain)
+                               irq_domain_remove(port->msi_domain);
+                       if (port->inner_domain)
+                               irq_domain_remove(port->inner_domain);
+               }
+
+               irq_dispose_mapping(port->irq);
+       }
+}
+
 static int mtk_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
                             irq_hw_number_t hwirq)
 {
@@ -1171,6 +1193,31 @@ static int mtk_pcie_probe(struct platform_device *pdev)
        return err;
 }
 
+
+static void mtk_pcie_free_resources(struct mtk_pcie *pcie)
+{
+       struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
+       struct list_head *windows = &host->windows;
+
+       pci_free_resource_list(windows);
+}
+
+static int mtk_pcie_remove(struct platform_device *pdev)
+{
+       struct mtk_pcie *pcie = platform_get_drvdata(pdev);
+       struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
+
+       pci_stop_root_bus(host->bus);
+       pci_remove_root_bus(host->bus);
+       mtk_pcie_free_resources(pcie);
+
+       mtk_pcie_irq_teardown(pcie);
+
+       mtk_pcie_put_resources(pcie);
+
+       return 0;
+}
+
 static int __maybe_unused mtk_pcie_suspend_noirq(struct device *dev)
 {
        struct mtk_pcie *pcie = dev_get_drvdata(dev);
@@ -1248,6 +1295,7 @@ static const struct of_device_id mtk_pcie_ids[] = {
 
 static struct platform_driver mtk_pcie_driver = {
        .probe = mtk_pcie_probe,
+       .remove = mtk_pcie_remove,
        .driver = {
                .name = "mtk-pcie",
                .of_match_table = mtk_pcie_ids,
@@ -1255,4 +1303,5 @@ static struct platform_driver mtk_pcie_driver = {
                .pm = &mtk_pcie_pm_ops,
        },
 };
-builtin_platform_driver(mtk_pcie_driver);
+module_platform_driver(mtk_pcie_driver);
+MODULE_LICENSE("GPL v2");
-- 
2.6.4