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+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test for the FPGA Bridge
+ *
+ * Copyright (C) 2023 Red Hat, Inc.
+ *
+ * Author: Marco Pagani <marpagan@redhat.com>
+ */
+
+#include <kunit/test.h>
+#include <linux/device.h>
+#include <linux/fpga/fpga-bridge.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+struct bridge_stats {
+ bool enable;
+};
+
+struct bridge_ctx {
+ struct fpga_bridge *bridge;
+ struct platform_device *pdev;
+ struct bridge_stats stats;
+};
+
+static int op_enable_set(struct fpga_bridge *bridge, bool enable)
+{
+ struct bridge_stats *stats = bridge->priv;
+
+ stats->enable = enable;
+
+ return 0;
+}
+
+/*
+ * Fake Bridge that implements only the enable_set op to track
+ * the state.
+ */
+static const struct fpga_bridge_ops fake_bridge_ops = {
+ .enable_set = op_enable_set,
+};
+
+/**
+ * register_test_bridge() - Register a fake Bridge for testing.
+ * @test: KUnit test context object.
+ *
+ * Return: Context of the newly registered Bridge.
+ */
+static struct bridge_ctx *register_test_bridge(struct kunit *test)
+{
+ struct bridge_ctx *ctx;
+
+ ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
+ ctx->pdev = platform_device_register_simple("bridge_pdev", PLATFORM_DEVID_AUTO, NULL, 0);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx->pdev);
+
+ ctx->bridge = fpga_bridge_register(&ctx->pdev->dev, "Fake FPGA Bridge", &fake_bridge_ops,
+ &ctx->stats);
+ KUNIT_ASSERT_FALSE(test, IS_ERR_OR_NULL(ctx->bridge));
+
+ return ctx;
+}
+
+static void unregister_test_bridge(struct bridge_ctx *ctx)
+{
+ fpga_bridge_unregister(ctx->bridge);
+ platform_device_unregister(ctx->pdev);
+}
+
+static void fpga_bridge_test_get(struct kunit *test)
+{
+ struct bridge_ctx *ctx = test->priv;
+ struct fpga_bridge *bridge;
+
+ bridge = fpga_bridge_get(&ctx->pdev->dev, NULL);
+ KUNIT_EXPECT_PTR_EQ(test, bridge, ctx->bridge);
+
+ bridge = fpga_bridge_get(&ctx->pdev->dev, NULL);
+ KUNIT_EXPECT_EQ(test, PTR_ERR(bridge), -EBUSY);
+
+ fpga_bridge_put(ctx->bridge);
+}
+
+static void fpga_bridge_test_toggle(struct kunit *test)
+{
+ struct bridge_ctx *ctx = test->priv;
+ int ret;
+
+ ret = fpga_bridge_disable(ctx->bridge);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+ KUNIT_EXPECT_FALSE(test, ctx->stats.enable);
+
+ ret = fpga_bridge_enable(ctx->bridge);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+ KUNIT_EXPECT_TRUE(test, ctx->stats.enable);
+}
+
+/* Test the functions for getting and controlling a list of bridges */
+static void fpga_bridge_test_get_put_list(struct kunit *test)
+{
+ struct list_head bridge_list;
+ struct bridge_ctx *ctx_0, *ctx_1;
+ int ret;
+
+ ctx_0 = test->priv;
+ ctx_1 = register_test_bridge(test);
+
+ INIT_LIST_HEAD(&bridge_list);
+
+ /* Get bridge 0 and add it to the list */
+ ret = fpga_bridge_get_to_list(&ctx_0->pdev->dev, NULL, &bridge_list);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+
+ KUNIT_EXPECT_PTR_EQ(test, ctx_0->bridge,
+ list_first_entry_or_null(&bridge_list, struct fpga_bridge, node));
+
+ /* Get bridge 1 and add it to the list */
+ ret = fpga_bridge_get_to_list(&ctx_1->pdev->dev, NULL, &bridge_list);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+
+ KUNIT_EXPECT_PTR_EQ(test, ctx_1->bridge,
+ list_first_entry_or_null(&bridge_list, struct fpga_bridge, node));
+
+ /* Disable an then enable both bridges from the list */
+ ret = fpga_bridges_disable(&bridge_list);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+
+ KUNIT_EXPECT_FALSE(test, ctx_0->stats.enable);
+ KUNIT_EXPECT_FALSE(test, ctx_1->stats.enable);
+
+ ret = fpga_bridges_enable(&bridge_list);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+
+ KUNIT_EXPECT_TRUE(test, ctx_0->stats.enable);
+ KUNIT_EXPECT_TRUE(test, ctx_1->stats.enable);
+
+ /* Put and remove both bridges from the list */
+ fpga_bridges_put(&bridge_list);
+
+ KUNIT_EXPECT_TRUE(test, list_empty(&bridge_list));
+
+ unregister_test_bridge(ctx_1);
+}
+
+static int fpga_bridge_test_init(struct kunit *test)
+{
+ test->priv = register_test_bridge(test);
+
+ return 0;
+}
+
+static void fpga_bridge_test_exit(struct kunit *test)
+{
+ unregister_test_bridge(test->priv);
+}
+
+static struct kunit_case fpga_bridge_test_cases[] = {
+ KUNIT_CASE(fpga_bridge_test_get),
+ KUNIT_CASE(fpga_bridge_test_toggle),
+ KUNIT_CASE(fpga_bridge_test_get_put_list),
+ {}
+};
+
+static struct kunit_suite fpga_bridge_suite = {
+ .name = "fpga_bridge",
+ .init = fpga_bridge_test_init,
+ .exit = fpga_bridge_test_exit,
+ .test_cases = fpga_bridge_test_cases,
+};
+
+kunit_test_suite(fpga_bridge_suite);
+
+MODULE_LICENSE("GPL");