1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef COMPONENT_H
3#define COMPONENT_H
4
5#include <linux/stddef.h>
6#include <linux/types.h>
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 *);
93bool component_master_is_bound(struct device *parent,
94 const struct component_master_ops *ops);
95
96struct component_match;
97
98int component_master_add_with_match(struct device *,
99 const struct component_master_ops *, struct component_match *);
100void component_match_add_release(struct device *parent,
101 struct component_match **matchptr,
102 void (*release)(struct device *, void *),
103 int (*compare)(struct device *, void *), void *compare_data);
104void component_match_add_typed(struct device *parent,
105 struct component_match **matchptr,
106 int (*compare_typed)(struct device *, int, void *), void *compare_data);
107
108/**
109 * component_match_add - add a component match entry
110 * @parent: device with the aggregate driver
111 * @matchptr: pointer to the list of component matches
112 * @compare: compare function to match against all components
113 * @compare_data: opaque pointer passed to the @compare function
114 *
115 * Adds a new component match to the list stored in @matchptr, which the @parent
116 * aggregate driver needs to function. The list of component matches pointed to
117 * by @matchptr must be initialized to NULL before adding the first match. This
118 * only matches against components added with component_add().
119 *
120 * The allocated match list in @matchptr is automatically released using devm
121 * actions.
122 *
123 * See also component_match_add_release() and component_match_add_typed().
124 */
125static inline void component_match_add(struct device *parent,
126 struct component_match **matchptr,
127 int (*compare)(struct device *, void *), void *compare_data)
128{
129 component_match_add_release(parent, matchptr, NULL, compare,
130 compare_data);
131}
132
133#endif
134