[PATCH v2] PCI: qcom: Add support for modular builds

[Johan Hovold <johan+linaro@kernel.org>]

Allow the Qualcomm PCIe controller driver to be built as a module, which
is useful for multi-platform kernels as well as during development.

Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---

Changes in v2
 - rebase on next-20220720 (adjust context)
 - add Rob and Mani's reviewed-by tags


 drivers/pci/controller/dwc/Kconfig     |  2 +-
 drivers/pci/controller/dwc/pcie-qcom.c | 36 +++++++++++++++++++++++---
 2 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
index 62ce3abf0f19..230f56d1a268 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -168,7 +168,7 @@ config PCI_HISI
 	  Hip05 and Hip06 SoCs
 
 config PCIE_QCOM
-	bool "Qualcomm PCIe controller"
+	tristate "Qualcomm PCIe controller"
 	depends on OF && (ARCH_QCOM || COMPILE_TEST)
 	depends on PCI_MSI_IRQ_DOMAIN
 	select PCIE_DW_HOST
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 5ed164c2afa3..d176c635016b 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -16,7 +16,7 @@
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/kernel.h>
-#include <linux/init.h>
+#include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/of_gpio.h>
 #include <linux/pci.h>
@@ -1518,6 +1518,15 @@ static int qcom_pcie_host_init(struct dw_pcie_rp *pp)
 	return ret;
 }
 
+static void qcom_pcie_host_deinit(struct qcom_pcie *pcie)
+{
+	qcom_ep_reset_assert(pcie);
+	if (pcie->cfg->ops->post_deinit)
+		pcie->cfg->ops->post_deinit(pcie);
+	phy_power_off(pcie->phy);
+	pcie->cfg->ops->deinit(pcie);
+}
+
 static const struct dw_pcie_host_ops qcom_pcie_dw_ops = {
 	.host_init = qcom_pcie_host_init,
 };
@@ -1752,6 +1761,22 @@ static int qcom_pcie_probe(struct platform_device *pdev)
 	return ret;
 }
 
+static int qcom_pcie_remove(struct platform_device *pdev)
+{
+	struct qcom_pcie *pcie = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+
+	dw_pcie_host_deinit(&pcie->pci->pp);
+	qcom_pcie_host_deinit(pcie);
+
+	phy_exit(pcie->phy);
+
+	pm_runtime_put_sync(dev);
+	pm_runtime_disable(dev);
+
+	return 0;
+}
+
 static const struct of_device_id qcom_pcie_match[] = {
 	{ .compatible = "qcom,pcie-apq8084", .data = &apq8084_cfg },
 	{ .compatible = "qcom,pcie-ipq8064", .data = &ipq8064_cfg },
@@ -1771,6 +1796,7 @@ static const struct of_device_id qcom_pcie_match[] = {
 	{ .compatible = "qcom,pcie-ipq6018", .data = &ipq6018_cfg },
 	{ }
 };
+MODULE_DEVICE_TABLE(of, qcom_pcie_match);
 
 static void qcom_fixup_class(struct pci_dev *dev)
 {
@@ -1786,10 +1812,14 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_QCOM, 0x1001, qcom_fixup_class);
 
 static struct platform_driver qcom_pcie_driver = {
 	.probe = qcom_pcie_probe,
+	.remove = qcom_pcie_remove,
 	.driver = {
 		.name = "qcom-pcie",
-		.suppress_bind_attrs = true,
 		.of_match_table = qcom_pcie_match,
 	},
 };
-builtin_platform_driver(qcom_pcie_driver);
+module_platform_driver(qcom_pcie_driver);
+
+MODULE_AUTHOR("Stanimir Varbanov <svarbanov@mm-sol.com>");
+MODULE_DESCRIPTION("Qualcomm PCIe root complex driver");
+MODULE_LICENSE("GPL");
-- 
2.35.1