[PATCH v2 2/7] clk: tests: Add clk_parse_clkspec() Kunit testing

["Miquel Raynal (Schneider Electric)" <miquel.raynal@bootlin.com>]

Create a new set of kunit tests to make sure clk_parse_clkspec() is
working as expected. We currently verify if we get a proper device when
using indexes and names. If we make an out of bounds request we expect
an error.

For testing purposes, we must ensure of_clk_get_hw()'s symbol is
exported.

Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Miquel Raynal (Schneider Electric) <miquel.raynal@bootlin.com>
---
 drivers/clk/Makefile                     |   1 +
 drivers/clk/clk.c                        |   2 +
 drivers/clk/clk_test.c                   | 117 +++++++++++++++++++++++++++++++
 drivers/clk/kunit_clk_parse_clkspec.dtso |  21 ++++++
 4 files changed, 141 insertions(+)

diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index cc108a75a900..035b984db70d 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -19,6 +19,7 @@ clk-test-y			:= clk_test.o \
 				   kunit_clk_assigned_rates_zero.dtbo.o \
 				   kunit_clk_assigned_rates_zero_consumer.dtbo.o \
 				   kunit_clk_hw_get_dev_of_node.dtbo.o \
+				   kunit_clk_parse_clkspec.dtbo.o \
 				   kunit_clk_parent_data_test.dtbo.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-divider.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-fixed-factor.o
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 048adfa86a5d..08874cf9b561 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -24,6 +24,7 @@
 #include <linux/spinlock.h>
 #include <linux/string.h>
 #include <linux/stringhash.h>
+#include <kunit/visibility.h>
 
 #include "clk.h"
 
@@ -5300,6 +5301,7 @@ struct clk_hw *of_clk_get_hw(struct device_node *np, int index,
 
 	return hw;
 }
+EXPORT_SYMBOL_IF_KUNIT(of_clk_get_hw);
 
 static struct clk *__of_clk_get(struct device_node *np,
 				int index, const char *dev_id,
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index b1961daac5e2..fddb2bb9618f 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -3541,10 +3541,126 @@ static struct kunit_suite clk_hw_get_dev_of_node_test_suite = {
 	.test_cases = clk_hw_get_dev_of_node_test_cases,
 };
 
+static const struct clk_init_data clk_parse_clkspec_1_init_data = {
+	.name = "clk_parse_clkspec_1",
+	.ops = &empty_clk_ops,
+};
+
+static const struct clk_init_data clk_parse_clkspec_2_init_data = {
+	.name = "clk_parse_clkspec_2",
+	.ops = &empty_clk_ops,
+};
+
+struct clk_parse_clkspec_ctx {
+	struct device_node *cons_np;
+};
+
+static int clk_parse_clkspec_init(struct kunit *test)
+{
+	struct device_node *prov1_np, *prov2_np;
+	struct clk_parse_clkspec_ctx *ctx;
+	struct clk_hw *hw1, *hw2;
+
+	ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+	test->priv = ctx;
+
+	KUNIT_ASSERT_EQ(test, 0, of_overlay_apply_kunit(test, kunit_clk_parse_clkspec));
+
+	/* Register provider 1 */
+	hw1 = kunit_kzalloc(test, sizeof(*hw1), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, hw1);
+	hw1->init = &clk_parse_clkspec_1_init_data;
+
+	prov1_np = of_find_compatible_node(NULL, NULL, "test,clock-provider1");
+	KUNIT_ASSERT_NOT_NULL(test, prov1_np);
+
+	KUNIT_ASSERT_EQ(test, 0, of_clk_hw_register_kunit(test, prov1_np, hw1));
+	of_clk_add_hw_provider_kunit(test, prov1_np, of_clk_hw_simple_get, hw1);
+	of_node_put(prov1_np);
+
+	/* Register provider 2 */
+	hw2 = kunit_kzalloc(test, sizeof(*hw2), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, hw2);
+	hw2->init = &clk_parse_clkspec_2_init_data;
+
+	prov2_np = of_find_compatible_node(NULL, NULL, "test,clock-provider2");
+	KUNIT_ASSERT_NOT_NULL(test, prov2_np);
+
+	KUNIT_ASSERT_EQ(test, 0, of_clk_hw_register_kunit(test, prov2_np, hw2));
+	of_clk_add_hw_provider_kunit(test, prov2_np, of_clk_hw_simple_get, hw2);
+	of_node_put(prov2_np);
+
+	ctx->cons_np = of_find_compatible_node(NULL, NULL, "test,clock-consumer");
+	KUNIT_ASSERT_NOT_NULL(test, ctx->cons_np);
+
+	return 0;
+}
+
+static void clk_parse_clkspec_exit(struct kunit *test)
+{
+	struct clk_parse_clkspec_ctx *ctx = test->priv;
+
+	of_node_put(ctx->cons_np);
+}
+
+/* Test DT phandle lookups using correct index or name succeed */
+static void clk_parse_clkspec_with_correct_index_and_name(struct kunit *test)
+{
+	struct clk_parse_clkspec_ctx *ctx = test->priv;
+	struct clk_hw *hw1, *hw2, *hw3, *hw4;
+
+	/* Get clocks by index */
+	hw1 = of_clk_get_hw(ctx->cons_np, 0, NULL);
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, hw1);
+
+	hw2 = of_clk_get_hw(ctx->cons_np, 1, NULL);
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, hw2);
+	KUNIT_EXPECT_PTR_NE(test, hw1, hw2);
+
+	/* Get clocks by name */
+	hw3 = of_clk_get_hw(ctx->cons_np, 0, "first_clock");
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, hw3);
+	KUNIT_EXPECT_PTR_EQ(test, hw1, hw3);
+
+	hw4 = of_clk_get_hw(ctx->cons_np, 0, "second_clock");
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, hw4);
+	KUNIT_EXPECT_PTR_EQ(test, hw2, hw4);
+}
+
+/* Test DT phandle lookups using wrong index or name fail */
+static void clk_parse_clkspec_with_incorrect_index_and_name(struct kunit *test)
+{
+	struct clk_parse_clkspec_ctx *ctx = test->priv;
+	struct clk_hw *hw;
+
+	/* Get clock by index */
+	hw = of_clk_get_hw(ctx->cons_np, 2, NULL);
+	KUNIT_EXPECT_TRUE(test, IS_ERR(hw));
+
+	/* Get clock by name */
+	hw = of_clk_get_hw(ctx->cons_np, 0, "third_clock");
+	KUNIT_EXPECT_TRUE(test, IS_ERR(hw));
+}
+
+static struct kunit_case clk_parse_clkspec_test_cases[] = {
+	KUNIT_CASE(clk_parse_clkspec_with_correct_index_and_name),
+	KUNIT_CASE(clk_parse_clkspec_with_incorrect_index_and_name),
+	{}
+};
+
+/* Test suite to verify clk_parse_clkspec() */
+static struct kunit_suite clk_parse_clkspec_test_suite = {
+	.name = "clk_parse_clkspec",
+	.init = clk_parse_clkspec_init,
+	.exit = clk_parse_clkspec_exit,
+	.test_cases = clk_parse_clkspec_test_cases,
+};
 
 kunit_test_suites(
 	&clk_assigned_rates_suite,
 	&clk_hw_get_dev_of_node_test_suite,
+	&clk_parse_clkspec_test_suite,
 	&clk_leaf_mux_set_rate_parent_test_suite,
 	&clk_test_suite,
 	&clk_multiple_parents_mux_test_suite,
@@ -3562,4 +3678,5 @@ kunit_test_suites(
 	&clk_uncached_test_suite,
 );
 MODULE_DESCRIPTION("Kunit tests for clk framework");
+MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/clk/kunit_clk_parse_clkspec.dtso b/drivers/clk/kunit_clk_parse_clkspec.dtso
new file mode 100644
index 000000000000..c93feb93e101
--- /dev/null
+++ b/drivers/clk/kunit_clk_parse_clkspec.dtso
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+/dts-v1/;
+/plugin/;
+
+&{/} {
+	kunit_clock_provider1: kunit-clock-provider1 {
+		compatible = "test,clock-provider1";
+		#clock-cells = <1>;
+	};
+
+	kunit_clock_provider2: kunit-clock-provider2 {
+		compatible = "test,clock-provider2";
+		#clock-cells = <1>;
+	};
+
+	kunit-clock-consumer {
+		compatible = "test,clock-consumer";
+		clocks = <&kunit_clock_provider1 0>, <&kunit_clock_provider2 0>;
+		clock-names = "first_clock", "second_clock";
+	};
+};

-- 
2.54.0