1 files changed, 90 insertions, 6 deletions

diff --git a/include/linux/component.h b/include/linux/component.h
index e71fbbbc74e2..9d6c66401280 100644
--- a/include/linux/component.h
+++ b/include/linux/component.h
@@ -3,46 +3,130 @@
 #define COMPONENT_H
 
 #include <linux/stddef.h>
+#include <linux/types.h>
 
 struct device;
 
+/**
+ * struct component_ops - callbacks for component drivers
+ *
+ * Components are registered with component_add() and unregistered with
+ * component_del().
+ */
 struct component_ops {
+	/**
+	 * @bind:
+	 *
+	 * Called through component_bind_all() when the aggregate driver is
+	 * ready to bind the overall driver.
+	 */
 	int (*bind)(struct device *comp, struct device *master,
 		    void *master_data);
+	/**
+	 * @unbind:
+	 *
+	 * Called through component_unbind_all() when the aggregate driver is
+	 * ready to bind the overall driver, or when component_bind_all() fails
+	 * part-ways through and needs to unbind some already bound components.
+	 */
 	void (*unbind)(struct device *comp, struct device *master,
 		       void *master_data);
 };
 
 int component_add(struct device *, const struct component_ops *);
+int component_add_typed(struct device *dev, const struct component_ops *ops,
+	int subcomponent);
 void component_del(struct device *, const struct component_ops *);
 
-int component_bind_all(struct device *master, void *master_data);
-void component_unbind_all(struct device *master, void *master_data);
+int component_bind_all(struct device *parent, void *data);
+void component_unbind_all(struct device *parent, void *data);
 
-struct master;
+struct aggregate_device;
 
+/**
+ * struct component_master_ops - callback for the aggregate driver
+ *
+ * Aggregate drivers are registered with component_master_add_with_match() and
+ * unregistered with component_master_del().
+ */
 struct component_master_ops {
+	/**
+	 * @bind:
+	 *
+	 * Called when all components or the aggregate driver, as specified in
+	 * the match list passed to component_master_add_with_match(), are
+	 * ready. Usually there are 3 steps to bind an aggregate driver:
+	 *
+	 * 1. Allocate a structure for the aggregate driver.
+	 *
+	 * 2. Bind all components to the aggregate driver by calling
+	 *    component_bind_all() with the aggregate driver structure as opaque
+	 *    pointer data.
+	 *
+	 * 3. Register the aggregate driver with the subsystem to publish its
+	 *    interfaces.
+	 *
+	 * Note that the lifetime of the aggregate driver does not align with
+	 * any of the underlying &struct device instances. Therefore devm cannot
+	 * be used and all resources acquired or allocated in this callback must
+	 * be explicitly released in the @unbind callback.
+	 */
 	int (*bind)(struct device *master);
+	/**
+	 * @unbind:
+	 *
+	 * Called when either the aggregate driver, using
+	 * component_master_del(), or one of its components, using
+	 * component_del(), is unregistered.
+	 */
 	void (*unbind)(struct device *master);
 };
 
+/* A set helper functions for component compare/release */
+int component_compare_of(struct device *dev, void *data);
+void component_release_of(struct device *dev, void *data);
+int component_compare_dev(struct device *dev, void *data);
+int component_compare_dev_name(struct device *dev, void *data);
+
 void component_master_del(struct device *,
 	const struct component_master_ops *);
+bool component_master_is_bound(struct device *parent,
+	const struct component_master_ops *ops);
 
 struct component_match;
 
 int component_master_add_with_match(struct device *,
 	const struct component_master_ops *, struct component_match *);
-void component_match_add_release(struct device *master,
+void component_match_add_release(struct device *parent,
 	struct component_match **matchptr,
 	void (*release)(struct device *, void *),
 	int (*compare)(struct device *, void *), void *compare_data);
+void component_match_add_typed(struct device *parent,
+	struct component_match **matchptr,
+	int (*compare_typed)(struct device *, int, void *), void *compare_data);
 
-static inline void component_match_add(struct device *master,
+/**
+ * component_match_add - add a component match entry
+ * @parent: device with the aggregate driver
+ * @matchptr: pointer to the list of component matches
+ * @compare: compare function to match against all components
+ * @compare_data: opaque pointer passed to the @compare function
+ *
+ * Adds a new component match to the list stored in @matchptr, which the @parent
+ * aggregate driver needs to function. The list of component matches pointed to
+ * by @matchptr must be initialized to NULL before adding the first match. This
+ * only matches against components added with component_add().
+ *
+ * The allocated match list in @matchptr is automatically released using devm
+ * actions.
+ *
+ * See also component_match_add_release() and component_match_add_typed().
+ */
+static inline void component_match_add(struct device *parent,
 	struct component_match **matchptr,
 	int (*compare)(struct device *, void *), void *compare_data)
 {
-	component_match_add_release(master, matchptr, NULL, compare,
+	component_match_add_release(parent, matchptr, NULL, compare,
 				    compare_data);
 }