at v6.15 4.6 kB view raw
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