1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef COMPONENT_H
3#define COMPONENT_H
4
5#include <linux/stddef.h>
6
7
8struct device;
9
10/**
11 * struct component_ops - callbacks for component drivers
12 *
13 * Components are registered with component_add() and unregistered with
14 * component_del().
15 */
16struct component_ops {
17	/**
18	 * @bind:
19	 *
20	 * Called through component_bind_all() when the aggregate driver is
21	 * ready to bind the overall driver.
22	 */
23	int (*bind)(struct device *comp, struct device *master,
24		    void *master_data);
25	/**
26	 * @unbind:
27	 *
28	 * Called through component_unbind_all() when the aggregate driver is
29	 * ready to bind the overall driver, or when component_bind_all() fails
30	 * part-ways through and needs to unbind some already bound components.
31	 */
32	void (*unbind)(struct device *comp, struct device *master,
33		       void *master_data);
34};
35
36int component_add(struct device *, const struct component_ops *);
37int component_add_typed(struct device *dev, const struct component_ops *ops,
38	int subcomponent);
39void component_del(struct device *, const struct component_ops *);
40
41int component_bind_all(struct device *parent, void *data);
42void component_unbind_all(struct device *parent, void *data);
43
44struct aggregate_device;
45
46/**
47 * struct component_master_ops - callback for the aggregate driver
48 *
49 * Aggregate drivers are registered with component_master_add_with_match() and
50 * unregistered with component_master_del().
51 */
52struct component_master_ops {
53	/**
54	 * @bind:
55	 *
56	 * Called when all components or the aggregate driver, as specified in
57	 * the match list passed to component_master_add_with_match(), are
58	 * ready. Usually there are 3 steps to bind an aggregate driver:
59	 *
60	 * 1. Allocate a structure for the aggregate driver.
61	 *
62	 * 2. Bind all components to the aggregate driver by calling
63	 *    component_bind_all() with the aggregate driver structure as opaque
64	 *    pointer data.
65	 *
66	 * 3. Register the aggregate driver with the subsystem to publish its
67	 *    interfaces.
68	 *
69	 * Note that the lifetime of the aggregate driver does not align with
70	 * any of the underlying &struct device instances. Therefore devm cannot
71	 * be used and all resources acquired or allocated in this callback must
72	 * be explicitly released in the @unbind callback.
73	 */
74	int (*bind)(struct device *master);
75	/**
76	 * @unbind:
77	 *
78	 * Called when either the aggregate driver, using
79	 * component_master_del(), or one of its components, using
80	 * component_del(), is unregistered.
81	 */
82	void (*unbind)(struct device *master);
83};
84
85/* A set helper functions for component compare/release */
86int component_compare_of(struct device *dev, void *data);
87void component_release_of(struct device *dev, void *data);
88int component_compare_dev(struct device *dev, void *data);
89int component_compare_dev_name(struct device *dev, void *data);
90
91void component_master_del(struct device *,
92	const struct component_master_ops *);
93
94struct component_match;
95
96int component_master_add_with_match(struct device *,
97	const struct component_master_ops *, struct component_match *);
98void component_match_add_release(struct device *parent,
99	struct component_match **matchptr,
100	void (*release)(struct device *, void *),
101	int (*compare)(struct device *, void *), void *compare_data);
102void component_match_add_typed(struct device *parent,
103	struct component_match **matchptr,
104	int (*compare_typed)(struct device *, int, void *), void *compare_data);
105
106/**
107 * component_match_add - add a component match entry
108 * @parent: device with the aggregate driver
109 * @matchptr: pointer to the list of component matches
110 * @compare: compare function to match against all components
111 * @compare_data: opaque pointer passed to the @compare function
112 *
113 * Adds a new component match to the list stored in @matchptr, which the @parent
114 * aggregate driver needs to function. The list of component matches pointed to
115 * by @matchptr must be initialized to NULL before adding the first match. This
116 * only matches against components added with component_add().
117 *
118 * The allocated match list in @matchptr is automatically released using devm
119 * actions.
120 *
121 * See also component_match_add_release() and component_match_add_typed().
122 */
123static inline void component_match_add(struct device *parent,
124	struct component_match **matchptr,
125	int (*compare)(struct device *, void *), void *compare_data)
126{
127	component_match_add_release(parent, matchptr, NULL, compare,
128				    compare_data);
129}
130
131#endif
132