[v3,08/11] clk: Add test managed clk provider/consumer APIs

diff --git a/Documentation/dev-tools/kunit/api/clk.rst b/Documentation/dev-tools/kunit/api/clk.rst
new file mode 100644
index 000000000000..badd87a35f9e
--- /dev/null
+++ b/Documentation/dev-tools/kunit/api/clk.rst
@@ -0,0 +1,10 @@ 
+.. SPDX-License-Identifier: GPL-2.0
+
+========
+Clk API
+========
+
+The KUnit clk API is used to test clk providers and clk consumers.
+
+.. kernel-doc:: drivers/clk/clk_kunit.c
+   :export:
diff --git a/Documentation/dev-tools/kunit/api/index.rst b/Documentation/dev-tools/kunit/api/index.rst
index eb628cb2c72a..cbde5f8d40e2 100644
--- a/Documentation/dev-tools/kunit/api/index.rst
+++ b/Documentation/dev-tools/kunit/api/index.rst
@@ -9,6 +9,7 @@  API Reference
 	test
 	resource
 	functionredirection
+	clk
 	of
 	platformdevice
 
@@ -34,6 +35,10 @@  Documentation/dev-tools/kunit/api/functionredirection.rst
 Driver KUnit API
 ================
 
+Documentation/dev-tools/kunit/api/clk.rst
+
+ - Documents the KUnit clk API
+
 Documentation/dev-tools/kunit/api/of.rst
 
  - Documents the KUnit device tree (OF) API
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index e3ca0d058a25..226b4b729703 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -17,6 +17,11 @@  ifeq ($(CONFIG_OF), y)
 obj-$(CONFIG_COMMON_CLK)	+= clk-conf.o
 endif
 
+# KUnit specific helpers
+ifeq ($(CONFIG_COMMON_CLK), y)
+obj-$(CONFIG_KUNIT)		+= clk_kunit.o
+endif
+
 # hardware specific clock types
 # please keep this section sorted lexicographically by file path name
 obj-$(CONFIG_COMMON_CLK_APPLE_NCO)  	+= clk-apple-nco.o
diff --git a/drivers/clk/clk_kunit.c b/drivers/clk/clk_kunit.c
new file mode 100644
index 000000000000..bb9bf5a2617f
--- /dev/null
+++ b/drivers/clk/clk_kunit.c
@@ -0,0 +1,224 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit helpers for clk providers and consumers
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include <kunit/clk.h>
+#include <kunit/resource.h>
+
+static void clk_disable_unprepare_kunit(struct kunit_resource *res)
+{
+	struct clk *clk = res->data;
+
+	clk_disable_unprepare(clk);
+}
+
+/**
+ * clk_prepare_enable_kunit() - Test managed clk_prepare_enable()
+ * @test: The test context
+ * @clk: clk to prepare and enable
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int clk_prepare_enable_kunit(struct kunit *test, struct clk *clk)
+{
+	if (!kunit_alloc_resource(test, NULL, clk_disable_unprepare_kunit,
+				  GFP_KERNEL, clk))
+		return -EINVAL;
+
+	return clk_prepare_enable(clk);
+}
+EXPORT_SYMBOL_GPL(clk_prepare_enable_kunit);
+
+static void clk_put_kunit(struct kunit_resource *res)
+{
+	struct clk *clk = res->data;
+
+	clk_put(clk);
+}
+
+static struct clk *__clk_get_kunit(struct kunit *test, struct clk *clk)
+{
+	if (IS_ERR(clk))
+		return clk;
+
+	if (!kunit_alloc_resource(test, NULL, clk_put_kunit, GFP_KERNEL, clk)) {
+		clk_put(clk);
+		return ERR_PTR(-EINVAL);
+	}
+
+	return clk;
+}
+
+/**
+ * clk_get_kunit() - Test managed clk_get()
+ * @test: The test context
+ * @dev: device for clock "consumer"
+ * @con_id: clock consumer ID
+ *
+ * Just like clk_get(), except the clk is managed by the test case and is
+ * automatically put with clk_put() after the test case concludes.
+ *
+ * Returns: new clk consumer or ERR_PTR on failure.
+ */
+struct clk *
+clk_get_kunit(struct kunit *test, struct device *dev, const char *con_id)
+{
+	struct clk *clk;
+
+	clk = clk_get(dev, con_id);
+
+	return __clk_get_kunit(test, clk);
+}
+EXPORT_SYMBOL_GPL(clk_get_kunit);
+
+/**
+ * of_clk_get_kunit() - Test managed of_clk_get()
+ * @test: The test context
+ * @np: device_node for clock "consumer"
+ * @index: index in 'clocks' property of @np
+ *
+ * Just like of_clk_get(), except the clk is managed by the test case and is
+ * automatically put with clk_put() after the test case concludes.
+ *
+ * Returns: new clk consumer or ERR_PTR on failure.
+ */
+struct clk *
+of_clk_get_kunit(struct kunit *test, struct device_node *np, int index)
+{
+	struct clk *clk;
+
+	clk = of_clk_get(np, index);
+
+	return __clk_get_kunit(test, clk);
+}
+EXPORT_SYMBOL_GPL(of_clk_get_kunit);
+
+/**
+ * clk_hw_get_clk_kunit() - Test managed clk_hw_get_clk()
+ * @test: The test context
+ * @hw: clk_hw associated with the clk being consumed
+ * @con_id: connection ID string on device
+ *
+ * Just like clk_hw_get_clk(), except the clk is managed by the test case and
+ * is automatically put with clk_put() after the test case concludes.
+ *
+ * Returns: new clk consumer or ERR_PTR on failure.
+ */
+struct clk *
+clk_hw_get_clk_kunit(struct kunit *test, struct clk_hw *hw, const char *con_id)
+{
+	struct clk *clk;
+
+	clk = clk_hw_get_clk(hw, con_id);
+
+	return __clk_get_kunit(test, clk);
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_clk_kunit);
+
+/**
+ * clk_hw_get_clk_prepared_enabled_kunit() - Test managed clk_hw_get_clk() + clk_prepare_enable()
+ * @test: The test context
+ * @hw: clk_hw associated with the clk being consumed
+ * @con_id: connection ID string on device
+ *
+ * Just like
+ *
+ * .. code-block:: c
+ *
+ *	struct clk *clk = clk_hw_get_clk(...);
+ *	clk_prepare_enable(clk);
+ *
+ * except the clk is managed by the test case and is automatically disabled and
+ * unprepared with clk_disable_unprepare() and put with clk_put() after the
+ * test case concludes.
+ *
+ * Returns: new clk consumer that is prepared and enabled or ERR_PTR on failure.
+ */
+struct clk *
+clk_hw_get_clk_prepared_enabled_kunit(struct kunit *test, struct clk_hw *hw,
+				      const char *con_id)
+{
+	int ret;
+	struct clk *clk;
+
+	clk = clk_hw_get_clk_kunit(test, hw, con_id);
+	if (IS_ERR(clk))
+		return clk;
+
+	ret = clk_prepare_enable_kunit(test, clk);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return clk;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_clk_prepared_enabled_kunit);
+
+static void clk_hw_unregister_kunit(struct kunit_resource *res)
+{
+	struct clk_hw *hw = res->data;
+
+	clk_hw_unregister(hw);
+}
+
+static int __clk_hw_register_kunit(struct kunit *test, struct clk_hw *hw)
+{
+	if (!kunit_alloc_resource(test, NULL, clk_hw_unregister_kunit, GFP_KERNEL, hw)) {
+		clk_hw_unregister(hw);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * clk_hw_register_kunit() - Test managed clk_hw_register()
+ * @test: The test context
+ * @dev: device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * Just like clk_hw_register(), except the clk registration is managed by the
+ * test case and is automatically unregistered after the test case concludes.
+ *
+ * Returns: 0 on success or a negative errno value on failure.
+ */
+int clk_hw_register_kunit(struct kunit *test, struct device *dev, struct clk_hw *hw)
+{
+	int ret;
+
+	ret = clk_hw_register(dev, hw);
+	if (ret)
+		return ret;
+
+	return __clk_hw_register_kunit(test, hw);
+}
+EXPORT_SYMBOL_GPL(clk_hw_register_kunit);
+
+/**
+ * of_clk_hw_register_kunit() - Test managed of_clk_hw_register()
+ * @test: The test context
+ * @node: device_node of device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * Just like of_clk_hw_register(), except the clk registration is managed by
+ * the test case and is automatically unregistered after the test case
+ * concludes.
+ *
+ * Returns: 0 on success or a negative errno value on failure.
+ */
+int of_clk_hw_register_kunit(struct kunit *test, struct device_node *node, struct clk_hw *hw)
+{
+	int ret;
+
+	ret = of_clk_hw_register(node, hw);
+	if (ret)
+		return ret;
+
+	return __clk_hw_register_kunit(test, hw);
+}
+EXPORT_SYMBOL_GPL(of_clk_hw_register_kunit);
diff --git a/include/kunit/clk.h b/include/kunit/clk.h
new file mode 100644
index 000000000000..73bc99cefe7b
--- /dev/null
+++ b/include/kunit/clk.h
@@ -0,0 +1,28 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _CLK_KUNIT_H
+#define _CLK_KUNIT_H
+
+struct clk;
+struct clk_hw;
+struct device;
+struct device_node;
+struct kunit;
+
+struct clk *
+clk_get_kunit(struct kunit *test, struct device *dev, const char *con_id);
+struct clk *
+of_clk_get_kunit(struct kunit *test, struct device_node *np, int index);
+
+struct clk *
+clk_hw_get_clk_kunit(struct kunit *test, struct clk_hw *hw, const char *con_id);
+struct clk *
+clk_hw_get_clk_prepared_enabled_kunit(struct kunit *test, struct clk_hw *hw,
+				      const char *con_id);
+
+int clk_prepare_enable_kunit(struct kunit *test, struct clk *clk);
+
+int clk_hw_register_kunit(struct kunit *test, struct device *dev, struct clk_hw *hw);
+int of_clk_hw_register_kunit(struct kunit *test, struct device_node *node,
+			     struct clk_hw *hw);
+
+#endif