[v3,1/4] clk: add a clk_hw helpers to get the clock device or device_node

Commit Message

Jerome Brunet Jan. 20, 2025, 5:15 p.m. UTC

Add helpers to get the device or device_node associated with clk_hw.

This can be used by clock drivers to access various device related
functionality such as devres, dev_ prints, etc ...

Add test for these new helpers in clk-test.

Signed-off-by: Jerome Brunet <[e-mail]>
---
 drivers/clk/Makefile                    |   1 +
 drivers/clk/clk.c                       |  33 +++++++++
 drivers/clk/clk_test.c                  | 116 +++++++++++++++++++++++++++-----
 drivers/clk/kunit_clk_dummy_device.dtso |  10 +++
 include/linux/clk-provider.h            |   2 +
 5 files changed, 145 insertions(+), 17 deletions(-)

Patch

diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index bf4bd45adc3a0ed8c9dc699c76f303dc91b524c4..b38ec888a449249340cd1ef147a774361558af3c 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -18,6 +18,7 @@  clk-test-y			:= clk_test.o \
 				   kunit_clk_assigned_rates_without_consumer.dtbo.o \
 				   kunit_clk_assigned_rates_zero.dtbo.o \
 				   kunit_clk_assigned_rates_zero_consumer.dtbo.o \
+				   kunit_clk_dummy_device.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 9b45fa005030f56e1478b9742715ebcde898133f..9818f87c1c56ab9a3782c2fd55d3f602041769c3 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -365,6 +365,39 @@  const char *clk_hw_get_name(const struct clk_hw *hw)
 }
 EXPORT_SYMBOL_GPL(clk_hw_get_name);
 
+/**
+ * clk_hw_get_dev - get device from an hardware clock.
+ * @hw: the clk_hw pointer to get the struct device from
+ *
+ * This is a helper to get the struct device associated with a hardware
+ * clock. Some clocks, such as the ones registered from an early clock
+ * controller, may not be associated with any struct device.
+ *
+ * Return: the struct device associated with the clock, or NULL if there
+ * is none.
+ */
+struct device *clk_hw_get_dev(const struct clk_hw *hw)
+{
+	return hw->core->dev;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_dev);
+
+/**
+ * clk_hw_get_of_node - get device_node from an hardware clock.
+ * @hw: the clk_hw pointer to get the struct device_node from
+ *
+ * This is a helper to get the struct device_node associated with an
+ * hardware clock.
+ *
+ * Return: the struct device_node associated with the clock, or NULL
+ * if there is none.
+ */
+struct device_node *clk_hw_get_of_node(const struct clk_hw *hw)
+{
+	return hw->core->of_node;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_of_node);
+
 struct clk_hw *__clk_get_hw(struct clk *clk)
 {
 	return !clk ? NULL : clk->core->hw;
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index f08feeaa3750bc86859294650de298762dea690a..4dcdde283598b7f940c653ebc0d5a5f4c27637a2 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -2794,43 +2794,40 @@  static struct kunit_suite clk_register_clk_parent_data_of_suite = {
 };
 
 /**
- * struct clk_register_clk_parent_data_device_ctx - Context for clk_parent_data device tests
+ * struct clk_register_device_ctx - Context for clock device tests
  * @dev: device of clk under test
  * @hw: clk_hw for clk under test
  * @pdrv: driver to attach to find @dev
  */
-struct clk_register_clk_parent_data_device_ctx {
+struct clk_register_device_ctx {
 	struct device *dev;
 	struct clk_hw hw;
 	struct platform_driver pdrv;
 };
 
-static inline struct clk_register_clk_parent_data_device_ctx *
-clk_register_clk_parent_data_driver_to_test_context(struct platform_device *pdev)
+static inline struct clk_register_device_ctx *
+clk_register_device_to_test_context(struct platform_device *pdev)
 {
 	return container_of(to_platform_driver(pdev->dev.driver),
-			    struct clk_register_clk_parent_data_device_ctx, pdrv);
+			    struct clk_register_device_ctx, pdrv);
 }
 
-static int clk_register_clk_parent_data_device_probe(struct platform_device *pdev)
+static int clk_register_device_probe(struct platform_device *pdev)
 {
-	struct clk_register_clk_parent_data_device_ctx *ctx;
+	struct clk_register_device_ctx *ctx;
 
-	ctx = clk_register_clk_parent_data_driver_to_test_context(pdev);
+	ctx = clk_register_device_to_test_context(pdev);
 	ctx->dev = &pdev->dev;
 
 	return 0;
 }
 
-static void clk_register_clk_parent_data_device_driver(struct kunit *test)
+static void clk_register_of_device_driver(struct kunit *test,
+					  const struct of_device_id *match_table)
 {
-	struct clk_register_clk_parent_data_device_ctx *ctx = test->priv;
-	static const struct of_device_id match_table[] = {
-		{ .compatible = "test,clk-parent-data" },
-		{ }
-	};
+	struct clk_register_device_ctx *ctx = test->priv;
 
-	ctx->pdrv.probe = clk_register_clk_parent_data_device_probe;
+	ctx->pdrv.probe = clk_register_device_probe;
 	ctx->pdrv.driver.of_match_table = match_table;
 	ctx->pdrv.driver.name = __func__;
 	ctx->pdrv.driver.owner = THIS_MODULE;
@@ -2839,6 +2836,16 @@  static void clk_register_clk_parent_data_device_driver(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx->dev);
 }
 
+static void clk_register_clk_parent_data_device_driver(struct kunit *test)
+{
+	static const struct of_device_id match_table[] = {
+		{ .compatible = "test,clk-parent-data" },
+		{ }
+	};
+
+	clk_register_of_device_driver(test, match_table);
+}
+
 static const struct clk_register_clk_parent_data_test_case
 clk_register_clk_parent_data_device_cases[] = {
 	{
@@ -2909,7 +2916,7 @@  KUNIT_ARRAY_PARAM(clk_register_clk_parent_data_device_test,
  */
 static void clk_register_clk_parent_data_device_test(struct kunit *test)
 {
-	struct clk_register_clk_parent_data_device_ctx *ctx;
+	struct clk_register_device_ctx *ctx;
 	const struct clk_register_clk_parent_data_test_case *test_param;
 	struct clk_hw *parent_hw;
 	struct clk_init_data init = { };
@@ -3016,7 +3023,7 @@  KUNIT_ARRAY_PARAM(clk_register_clk_parent_data_device_hw_test,
  */
 static void clk_register_clk_parent_data_device_hw_test(struct kunit *test)
 {
-	struct clk_register_clk_parent_data_device_ctx *ctx;
+	struct clk_register_device_ctx *ctx;
 	const struct clk_register_clk_parent_data_test_case *test_param;
 	struct clk_dummy_context *parent;
 	struct clk_hw *parent_hw;
@@ -3077,6 +3084,80 @@  static struct kunit_suite clk_register_clk_parent_data_device_suite = {
 	.test_cases = clk_register_clk_parent_data_device_test_cases,
 };
 
+static void clk_register_dummy_device_driver(struct kunit *test)
+{
+	static const struct of_device_id match_table[] = {
+		{ .compatible = "test,clk-dummy-device" },
+		{ }
+	};
+
+	clk_register_of_device_driver(test, match_table);
+}
+
+/*
+ * Test that a clk registered with a struct device can provide back the
+ * struct device it was registered with.
+ */
+static void clk_hw_get_dev_test(struct kunit *test)
+{
+	struct clk_register_device_ctx *ctx;
+
+	ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+	test->priv = ctx;
+
+	clk_register_dummy_device_driver(test);
+	ctx->hw.init = CLK_HW_INIT_NO_PARENT("test_get_dev",
+					     &clk_dummy_rate_ops, 0);
+
+	KUNIT_ASSERT_EQ(test, 0, clk_hw_register_kunit(test, ctx->dev, &ctx->hw));
+	KUNIT_EXPECT_PTR_EQ(test, ctx->dev, clk_hw_get_dev(&ctx->hw));
+}
+
+/*
+ * Test that a clk registered with a struct device_node can provide back the
+ * struct device_node it was registered with.
+ */
+static void clk_hw_get_of_node_test(struct kunit *test)
+{
+	struct device_node *np;
+	struct clk_hw *hw;
+
+	hw = kunit_kzalloc(test, sizeof(*hw), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, hw);
+
+	np = of_find_compatible_node(NULL, NULL, "test,clk-dummy-device");
+	hw->init = CLK_HW_INIT_NO_PARENT("test_get_of_node",
+					 &clk_dummy_rate_ops, 0);
+	of_node_put_kunit(test, np);
+
+	KUNIT_ASSERT_EQ(test, 0, of_clk_hw_register_kunit(test, np, hw));
+	KUNIT_EXPECT_PTR_EQ(test, np, clk_hw_get_of_node(hw));
+}
+
+static struct kunit_case clk_hw_test_cases[] = {
+	KUNIT_CASE(clk_hw_get_dev_test),
+	KUNIT_CASE(clk_hw_get_of_node_test),
+	{}
+};
+
+static int clk_hw_test_init(struct kunit *test)
+{
+	KUNIT_ASSERT_EQ(test, 0,
+			of_overlay_apply_kunit(test, kunit_clk_dummy_device));
+
+	return 0;
+}
+
+/*
+ * Test suite to verify the sanity clk_hw helper functions.
+ */
+static struct kunit_suite clk_hw_test_suite = {
+	.name = "clk_hw_test_suite",
+	.init = clk_hw_test_init,
+	.test_cases = clk_hw_test_cases,
+};
+
 struct clk_assigned_rates_context {
 	struct clk_dummy_context clk0;
 	struct clk_dummy_context clk1;
@@ -3399,6 +3480,7 @@  kunit_test_suites(
 	&clk_assigned_rates_suite,
 	&clk_leaf_mux_set_rate_parent_test_suite,
 	&clk_test_suite,
+	&clk_hw_test_suite,
 	&clk_multiple_parents_mux_test_suite,
 	&clk_mux_no_reparent_test_suite,
 	&clk_mux_notifier_test_suite,
diff --git a/drivers/clk/kunit_clk_dummy_device.dtso b/drivers/clk/kunit_clk_dummy_device.dtso
new file mode 100644
index 0000000000000000000000000000000000000000..5cc89aa11264428b09e47fd29c5f9ecfb8c32fdd
--- /dev/null
+++ b/drivers/clk/kunit_clk_dummy_device.dtso
@@ -0,0 +1,10 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/dts-v1/;
+/plugin/;
+
+&{/} {
+	kunit-clock-controller {
+		compatible = "test,clk-dummy-device";
+		#clock-cells = <0>;
+	};
+};
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 2e6e603b749342931c0d0693c3e72b62c000791b..83852346a32beae919d223f30cb88baa4b2fd62b 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -1360,6 +1360,8 @@  void clk_hw_unregister(struct clk_hw *hw);
 /* helper functions */
 const char *__clk_get_name(const struct clk *clk);
 const char *clk_hw_get_name(const struct clk_hw *hw);
+struct device *clk_hw_get_dev(const struct clk_hw *hw);
+struct device_node *clk_hw_get_of_node(const struct clk_hw *hw);
 #ifdef CONFIG_COMMON_CLK
 struct clk_hw *__clk_get_hw(struct clk *clk);
 #else