[RFC PATCH 07/21] PCI: endpoint: Add "pci-epf-bus" driver

[Kishon Vijay Abraham I]

Add "pci-epf-bus" driver that helps to create EPF device from
device tree. This is added in order to define an endpoint function
completely from device tree.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
 drivers/pci/endpoint/Makefile      |  3 +-
 drivers/pci/endpoint/pci-epf-bus.c | 54 ++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+), 1 deletion(-)
 create mode 100644 drivers/pci/endpoint/pci-epf-bus.c

diff --git a/drivers/pci/endpoint/Makefile b/drivers/pci/endpoint/Makefile
index 95b2fe47e3b0..36cf33cf975c 100644
--- a/drivers/pci/endpoint/Makefile
+++ b/drivers/pci/endpoint/Makefile
@@ -5,4 +5,5 @@
 
 obj-$(CONFIG_PCI_ENDPOINT_CONFIGFS)	+= pci-ep-cfs.o
 obj-$(CONFIG_PCI_ENDPOINT)		+= pci-epc-core.o pci-epf-core.o\
-					   pci-epc-mem.o functions/
+					   pci-epc-mem.o pci-epf-bus.o \
+					   functions/
diff --git a/drivers/pci/endpoint/pci-epf-bus.c b/drivers/pci/endpoint/pci-epf-bus.c
new file mode 100644
index 000000000000..c47eeae7fe7a
--- /dev/null
+++ b/drivers/pci/endpoint/pci-epf-bus.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+/**
+ * PCI Endpoint *Function* Bus Driver
+ *
+ * Copyright (C) 2019 Texas Instruments
+ * Author: Kishon Vijay Abraham I <kishon@xxxxxx>
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pci-epf.h>
+#include <linux/platform_device.h>
+
+static int pci_epf_bus_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *node = of_node_get(dev->of_node);
+	struct device_node *child;
+	struct pci_epf *epf;
+
+	for_each_child_of_node(node, child) {
+		epf = devm_pci_epf_of_create(dev, child);
+		if (IS_ERR(epf)) {
+			dev_err(dev, "Failed to create PCI EPF device %s\n",
+				node->full_name);
+			of_node_put(child);
+			break;
+		}
+	}
+	of_node_put(node);
+
+	return 0;
+}
+
+static const struct of_device_id pci_epf_bus_id_table[] = {
+	{ .compatible = "pci-epf-bus" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, pci_epf_bus_id_table);
+
+static struct platform_driver pci_epf_bus_driver = {
+	.probe		= pci_epf_bus_probe,
+	.driver		= {
+		.name	= "pci-epf-bus",
+		.of_match_table = of_match_ptr(pci_epf_bus_id_table),
+	},
+};
+
+module_platform_driver(pci_epf_bus_driver);
+
+MODULE_AUTHOR("Texas Instruments Inc.");
+MODULE_DESCRIPTION("PCI EPF Bus Driver");
+MODULE_LICENSE("GPL v2");
-- 
2.17.1