[6/8] clk: Add KUnit tests for clk fixed rate basic type

diff --git a/drivers/clk/.kunitconfig b/drivers/clk/.kunitconfig
index 2fbeb71316f8..3616cebd22f5 100644
--- a/drivers/clk/.kunitconfig
+++ b/drivers/clk/.kunitconfig
@@ -1,5 +1,8 @@ 
 CONFIG_KUNIT=y
+CONFIG_OF=y
+CONFIG_OF_KUNIT=y
 CONFIG_COMMON_CLK=y
 CONFIG_CLK_KUNIT_TEST=y
+CONFIG_CLK_FIXED_RATE_KUNIT_TEST=y
 CONFIG_CLK_GATE_KUNIT_TEST=y
 CONFIG_UML_PCI_OVER_VIRTIO=n
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index d79905f3e174..4849046b821f 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -479,6 +479,13 @@  config CLK_KUNIT_TEST
 	help
 	  Kunit tests for the common clock framework.
 
+config CLK_FIXED_RATE_KUNIT_TEST
+	tristate "Basic fixed rate clk type KUnit test" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  KUnit tests for the basic fixed rate clk type.
+
 config CLK_GATE_KUNIT_TEST
 	tristate "Basic gate type Kunit test" if !KUNIT_ALL_TESTS
 	depends on KUNIT
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 7efce649b0d3..e0689e9f73a4 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -6,6 +6,7 @@  obj-$(CONFIG_CLK_KUNIT_TEST)	+= clk_test.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-divider.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-fixed-factor.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-fixed-rate.o
+obj-$(CONFIG_CLK_FIXED_RATE_KUNIT_TEST)	+= clk-fixed-rate_test.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-gate.o
 obj-$(CONFIG_CLK_GATE_KUNIT_TEST) += clk-gate_test.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-multiplier.o
diff --git a/drivers/clk/clk-fixed-rate_test.c b/drivers/clk/clk-fixed-rate_test.c
new file mode 100644
index 000000000000..82e9e59a327c
--- /dev/null
+++ b/drivers/clk/clk-fixed-rate_test.c
@@ -0,0 +1,296 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test for clk fixed rate basic type
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+#include <kunit/platform_driver.h>
+#include <kunit/resource.h>
+#include <kunit/test.h>
+
+#include "clk-kunit.h"
+
+/**
+ * struct kunit_clk_hw_fixed_rate_params - Parameters to pass to __clk_hw_register_fixed_rate()
+ * @dev: device registering clk
+ * @np: device_node of device registering clk
+ * @name: name of clk
+ * @parent_name: parent name of clk
+ * @parent_hw: clk_hw pointer to parent of clk
+ * @parent_data: parent_data describing parent of clk
+ * @flags: clk framework flags
+ * @fixed_rate: frequency of clk
+ * @fixed_accuracy: accuracy of clk
+ * @clk_fixed_flags: fixed rate specific clk flags
+ */
+struct kunit_clk_hw_fixed_rate_params {
+	struct device *dev;
+	struct device_node *np;
+	const char *name;
+	const char *parent_name;
+	const struct clk_hw *parent_hw;
+	const struct clk_parent_data *parent_data;
+	unsigned long flags;
+	unsigned long fixed_rate;
+	unsigned long fixed_accuracy;
+	unsigned long clk_fixed_flags;
+};
+
+static int
+kunit_clk_hw_register_fixed_rate_init(struct kunit_resource *res, void *context)
+{
+	struct kunit_clk_hw_fixed_rate_params *params = context;
+	struct clk_hw *hw;
+
+	hw = __clk_hw_register_fixed_rate(params->dev, params->np,
+					  params->name,
+					  params->parent_name,
+					  params->parent_hw,
+					  params->parent_data,
+					  params->flags,
+					  params->fixed_rate,
+					  params->fixed_accuracy,
+					  params->clk_fixed_flags,
+					  false);
+	if (IS_ERR(hw))
+		return PTR_ERR(hw);
+
+	res->data = hw;
+
+	return 0;
+}
+
+static void kunit_clk_hw_register_fixed_rate_free(struct kunit_resource *res)
+{
+	struct clk_hw *hw = res->data;
+
+	clk_hw_unregister_fixed_rate(hw);
+}
+
+/**
+ * kunit_clk_hw_register_fixed_rate() - Test managed __clk_hw_register_fixed_rate()
+ * @test: The test context
+ * @params: Arguments to __clk_hw_register_fixed_rate()
+ *
+ * Returns: registered fixed rate clk_hw or ERR_PTR on failure.
+ */
+static struct clk_hw *
+kunit_clk_hw_register_fixed_rate(struct kunit *test, struct kunit_clk_hw_fixed_rate_params *params)
+{
+	struct clk_hw *hw;
+
+	hw = kunit_alloc_resource(test,
+				  kunit_clk_hw_register_fixed_rate_init,
+				  kunit_clk_hw_register_fixed_rate_free,
+				  GFP_KERNEL, params);
+	if (!hw)
+		return ERR_PTR(-EINVAL);
+
+	return hw;
+}
+
+/**
+ * kunit_clk_hw_unregister_fixed_rate() - Test managed clk_hw_unregister_fixed_rate()
+ * @test: The test context
+ * @hw: fixed rate clk to unregister upon test completion
+ *
+ * Automatically unregister @hw when @test is complete via
+ * clk_hw_unregister_fixed_rate().
+ *
+ * Returns: 0 on success or negative errno on failure
+ */
+static int kunit_clk_hw_unregister_fixed_rate(struct kunit *test, struct clk_hw *hw)
+{
+	if (!kunit_alloc_resource(test, NULL,
+				  kunit_clk_hw_register_fixed_rate_free,
+				  GFP_KERNEL, hw))
+		return -ENOMEM;
+
+	return 0;
+}
+
+/*
+ * Test that clk_get_rate() on a fixed rate clk registered with
+ * clk_hw_register_fixed_rate() gets the proper frequency.
+ */
+static void clk_fixed_rate_rate_test(struct kunit *test)
+{
+	struct clk_hw *hw;
+	struct clk *clk;
+	const unsigned long fixed_rate = 230000;
+
+	hw = clk_hw_register_fixed_rate(NULL, "test-fixed-rate", NULL, 0, fixed_rate);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, hw);
+	KUNIT_ASSERT_EQ(test, 0, kunit_clk_hw_unregister_fixed_rate(test, hw));
+
+	clk = kunit_clk_hw_get_clk_prepared_enabled(test, hw, __func__);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, clk);
+
+	KUNIT_EXPECT_EQ(test, fixed_rate, clk_get_rate(clk));
+}
+
+/*
+ * Test that clk_get_accuracy() on a fixed rate clk registered via
+ * clk_hw_register_fixed_rate_with_accuracy() gets the proper accuracy.
+ */
+static void clk_fixed_rate_accuracy_test(struct kunit *test)
+{
+	struct clk_hw *hw;
+	struct clk *clk;
+	const unsigned long fixed_accuracy = 5000;
+
+	hw = clk_hw_register_fixed_rate_with_accuracy(NULL, "test-fixed-rate",
+						      NULL, 0, 0,
+						      fixed_accuracy);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, hw);
+	KUNIT_ASSERT_EQ(test, 0, kunit_clk_hw_unregister_fixed_rate(test, hw));
+
+	clk = kunit_clk_hw_get_clk(test, hw, __func__);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, clk);
+
+	KUNIT_EXPECT_EQ(test, fixed_accuracy, clk_get_accuracy(clk));
+}
+
+/*
+ * Test that clk_get_parent() on a fixed rate clk gets the proper parent.
+ */
+static void clk_fixed_rate_parent_test(struct kunit *test)
+{
+	struct clk_hw *hw, *parent_hw;
+	struct clk *expected_parent, *actual_parent;
+	struct clk *clk;
+	const char *parent_name = "test-fixed-rate-parent";
+	struct kunit_clk_hw_fixed_rate_params parent_params = {
+		.name = parent_name,
+	};
+
+	parent_hw = kunit_clk_hw_register_fixed_rate(test, &parent_params);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, parent_hw);
+	KUNIT_ASSERT_STREQ(test, parent_name, clk_hw_get_name(parent_hw));
+
+	expected_parent = kunit_clk_hw_get_clk(test, parent_hw, __func__);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, expected_parent);
+
+	hw = clk_hw_register_fixed_rate(NULL, "test-fixed-rate", parent_name, 0, 0);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, hw);
+	KUNIT_ASSERT_EQ(test, 0, kunit_clk_hw_unregister_fixed_rate(test, hw));
+
+	clk = kunit_clk_hw_get_clk(test, hw, __func__);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, clk);
+
+	actual_parent = clk_get_parent(clk);
+	KUNIT_EXPECT_TRUE(test, clk_is_match(expected_parent, actual_parent));
+}
+
+static struct kunit_case clk_fixed_rate_test_cases[] = {
+	KUNIT_CASE(clk_fixed_rate_rate_test),
+	KUNIT_CASE(clk_fixed_rate_accuracy_test),
+	KUNIT_CASE(clk_fixed_rate_parent_test),
+	{}
+};
+
+static struct kunit_suite clk_fixed_rate_suite = {
+	.name = "clk_fixed_rate",
+	.test_cases = clk_fixed_rate_test_cases,
+};
+
+struct clk_fixed_rate_of_test_context {
+	struct device *dev;
+	struct platform_driver pdrv;
+};
+
+static inline struct clk_fixed_rate_of_test_context *
+pdev_to_clk_fixed_rate_of_test_context(struct platform_device *pdev)
+{
+	return container_of(to_platform_driver(pdev->dev.driver),
+			    struct clk_fixed_rate_of_test_context,
+			    pdrv);
+}
+
+/*
+ * Test that of_fixed_clk_setup() registers a fixed rate clk with the proper
+ * rate.
+ */
+static void clk_fixed_rate_of_probe_test(struct kunit *test)
+{
+	struct clk_fixed_rate_of_test_context *ctx = test->priv;
+	struct device *dev = ctx->dev;
+	struct clk *clk;
+
+	clk = kunit_clk_get(test, dev, NULL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, clk);
+
+	KUNIT_ASSERT_EQ(test, 0, kunit_clk_prepare_enable(test, clk));
+	KUNIT_EXPECT_EQ(test, 50000000, clk_get_rate(clk));
+}
+
+/*
+ * Test that of_fixed_clk_setup() registers a fixed rate clk with the proper
+ * accuracy.
+ */
+static void clk_fixed_rate_of_accuracy_test(struct kunit *test)
+{
+	struct clk_fixed_rate_of_test_context *ctx = test->priv;
+	struct device *dev = ctx->dev;
+	struct clk *clk;
+
+	clk = kunit_clk_get(test, dev, NULL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, clk);
+
+	KUNIT_EXPECT_EQ(test, 300, clk_get_accuracy(clk));
+}
+
+static struct kunit_case clk_fixed_rate_of_cases[] = {
+	KUNIT_CASE(clk_fixed_rate_of_probe_test),
+	KUNIT_CASE(clk_fixed_rate_of_accuracy_test),
+	{}
+};
+
+static int clk_fixed_rate_of_test_probe(struct platform_device *pdev)
+{
+	struct clk_fixed_rate_of_test_context *ctx;
+
+	ctx = pdev_to_clk_fixed_rate_of_test_context(pdev);
+	ctx->dev = &pdev->dev;
+
+	return 0;
+}
+
+static int clk_fixed_rate_of_init(struct kunit *test)
+{
+	struct clk_fixed_rate_of_test_context *ctx;
+	static const struct of_device_id match_table[] = {
+		{ .compatible = "linux,clk-kunit-fixed-rate" },
+		{ }
+	};
+
+	if (!IS_ENABLED(CONFIG_OF_KUNIT))
+		kunit_skip(test, "requires CONFIG_OF_KUNIT");
+
+	ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+	test->priv = ctx;
+
+	ctx->pdrv.probe = clk_fixed_rate_of_test_probe;
+	ctx->pdrv.driver.of_match_table = match_table;
+	ctx->pdrv.driver.name = __func__;
+	ctx->pdrv.driver.owner = THIS_MODULE;
+
+	return kunit_platform_driver_register(test, &ctx->pdrv);
+}
+
+static struct kunit_suite clk_fixed_rate_of_suite = {
+	.name = "clk_fixed_rate_of",
+	.init = clk_fixed_rate_of_init,
+	.test_cases = clk_fixed_rate_of_cases,
+};
+
+kunit_test_suites(
+	&clk_fixed_rate_suite,
+	&clk_fixed_rate_of_suite,
+);
+MODULE_LICENSE("GPL");
diff --git a/drivers/of/kunit/clk.dtsi b/drivers/of/kunit/clk.dtsi
new file mode 100644
index 000000000000..e3466bcfeb4b
--- /dev/null
+++ b/drivers/of/kunit/clk.dtsi
@@ -0,0 +1,15 @@ 
+// SPDX-License-Identifier: GPL-2.0
+
+/ {
+	fixed_50MHz: clock-50MHz {
+		compatible = "fixed-clock";
+		#clock-cells = <0>;
+		clock-frequency = <50000000>;
+		clock-accuracy = <300>;
+	};
+
+	clock-consumer-fixed-50 {
+		compatible = "linux,clk-kunit-fixed-rate";
+		clocks = <&fixed_50MHz>;
+	};
+};
diff --git a/drivers/of/kunit/kunit.dtsi b/drivers/of/kunit/kunit.dtsi
index 82f6c3e2b8d5..bce5bd8b9505 100644
--- a/drivers/of/kunit/kunit.dtsi
+++ b/drivers/of/kunit/kunit.dtsi
@@ -6,3 +6,4 @@  / {
 };
 
 /* Include testcase dtsi files below */
+#include "clk.dtsi"