[PATCH 4/4] PCI: mediatek: Add loadable kernel module support

From: honghui.zhang
Date: Wed Jun 27 2018 - 05:22:34 EST


From: Honghui Zhang <honghui.zhang@xxxxxxxxxxxx>

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

Signed-off-by: Honghui Zhang <honghui.zhang@xxxxxxxxxxxx>
Reviewed-by: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
---
drivers/pci/controller/Kconfig | 2 +-
drivers/pci/controller/pcie-mediatek.c | 63 +++++++++++++++++++++++++++++++---
2 files changed, 60 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 18fa09b..6c61ac65 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -234,7 +234,7 @@ 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 cac01ab..5830cea 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>
@@ -184,6 +185,7 @@ struct mtk_pcie_port {
struct phy *phy;
u32 lane;
u32 slot;
+ int irq;
struct irq_domain *irq_domain;
struct irq_domain *inner_domain;
struct irq_domain *msi_domain;
@@ -536,6 +538,30 @@ 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;
+
+ if (list_empty(&pcie->ports))
+ return;
+
+ 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)
{
@@ -626,7 +652,7 @@ static int mtk_pcie_setup_irq(struct mtk_pcie_port *port,
struct mtk_pcie *pcie = port->pcie;
struct device *dev = pcie->dev;
struct platform_device *pdev = to_platform_device(dev);
- int err, irq;
+ int err;

err = mtk_pcie_init_irq_domain(port, node);
if (err) {
@@ -634,8 +660,9 @@ static int mtk_pcie_setup_irq(struct mtk_pcie_port *port,
return err;
}

- irq = platform_get_irq(pdev, port->slot);
- irq_set_chained_handler_and_data(irq, mtk_pcie_intr_handler, port);
+ port->irq = platform_get_irq(pdev, port->slot);
+ irq_set_chained_handler_and_data(port->irq,
+ mtk_pcie_intr_handler, port);

return 0;
}
@@ -1197,6 +1224,32 @@ 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_unmap_iospace(&pcie->pio);
+ 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);
+
+ if (!list_empty(&pcie->ports))
+ mtk_pcie_put_resources(pcie);
+
+ return 0;
+}
+
#ifdef CONFIG_PM_SLEEP
static int mtk_pcie_suspend_noirq(struct device *dev)
{
@@ -1290,6 +1343,7 @@ 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,
@@ -1297,4 +1351,5 @@ 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