kernel/include/linux/component.h
2024-07-22 17:22:30 +08:00

126 lines
4.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef COMPONENT_H
#define COMPONENT_H
#include <linux/stddef.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);
struct master;
/**
* 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);
};
void component_master_del(struct device *,
const struct component_master_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,
struct component_match **matchptr,
void (*release)(struct device *, void *),
int (*compare)(struct device *, void *), void *compare_data);
void component_match_add_typed(struct device *master,
struct component_match **matchptr,
int (*compare_typed)(struct device *, int, void *), void *compare_data);
/**
* component_match_add - add a component match entry
* @master: 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 @master
* 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 *master,
struct component_match **matchptr,
int (*compare)(struct device *, void *), void *compare_data)
{
component_match_add_release(master, matchptr, NULL, compare,
compare_data);
}
#endif