xref: /openbmc/linux/drivers/base/base.h (revision 877013bc)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
4  * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
5  * Copyright (c) 2008-2012 Novell Inc.
6  * Copyright (c) 2012-2019 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7  * Copyright (c) 2012-2019 Linux Foundation
8  *
9  * Core driver model functions and structures that should not be
10  * shared outside of the drivers/base/ directory.
11  *
12  */
13 #include <linux/notifier.h>
14 
15 /**
16  * struct subsys_private - structure to hold the private to the driver core portions of the bus_type/class structure.
17  *
18  * @subsys - the struct kset that defines this subsystem
19  * @devices_kset - the subsystem's 'devices' directory
20  * @interfaces - list of subsystem interfaces associated
21  * @mutex - protect the devices, and interfaces lists.
22  *
23  * @drivers_kset - the list of drivers associated
24  * @klist_devices - the klist to iterate over the @devices_kset
25  * @klist_drivers - the klist to iterate over the @drivers_kset
26  * @bus_notifier - the bus notifier list for anything that cares about things
27  *                 on this bus.
28  * @bus - pointer back to the struct bus_type that this structure is associated
29  *        with.
30  *
31  * @glue_dirs - "glue" directory to put in-between the parent device to
32  *              avoid namespace conflicts
33  * @class - pointer back to the struct class that this structure is associated
34  *          with.
35  *
36  * This structure is the one that is the actual kobject allowing struct
37  * bus_type/class to be statically allocated safely.  Nothing outside of the
38  * driver core should ever touch these fields.
39  */
40 struct subsys_private {
41 	struct kset subsys;
42 	struct kset *devices_kset;
43 	struct list_head interfaces;
44 	struct mutex mutex;
45 
46 	struct kset *drivers_kset;
47 	struct klist klist_devices;
48 	struct klist klist_drivers;
49 	struct blocking_notifier_head bus_notifier;
50 	unsigned int drivers_autoprobe:1;
51 	struct bus_type *bus;
52 
53 	struct kset glue_dirs;
54 	struct class *class;
55 };
56 #define to_subsys_private(obj) container_of(obj, struct subsys_private, subsys.kobj)
57 
58 struct driver_private {
59 	struct kobject kobj;
60 	struct klist klist_devices;
61 	struct klist_node knode_bus;
62 	struct module_kobject *mkobj;
63 	struct device_driver *driver;
64 };
65 #define to_driver(obj) container_of(obj, struct driver_private, kobj)
66 
67 /**
68  * struct device_private - structure to hold the private to the driver core portions of the device structure.
69  *
70  * @klist_children - klist containing all children of this device
71  * @knode_parent - node in sibling list
72  * @knode_driver - node in driver list
73  * @knode_bus - node in bus list
74  * @knode_class - node in class list
75  * @deferred_probe - entry in deferred_probe_list which is used to retry the
76  *	binding of drivers which were unable to get all the resources needed by
77  *	the device; typically because it depends on another driver getting
78  *	probed first.
79  * @async_driver - pointer to device driver awaiting probe via async_probe
80  * @device - pointer back to the struct device that this structure is
81  * associated with.
82  * @dead - This device is currently either in the process of or has been
83  *	removed from the system. Any asynchronous events scheduled for this
84  *	device should exit without taking any action.
85  *
86  * Nothing outside of the driver core should ever touch these fields.
87  */
88 struct device_private {
89 	struct klist klist_children;
90 	struct klist_node knode_parent;
91 	struct klist_node knode_driver;
92 	struct klist_node knode_bus;
93 	struct klist_node knode_class;
94 	struct list_head deferred_probe;
95 	struct device_driver *async_driver;
96 	char *deferred_probe_reason;
97 	struct device *device;
98 	u8 dead:1;
99 };
100 #define to_device_private_parent(obj)	\
101 	container_of(obj, struct device_private, knode_parent)
102 #define to_device_private_driver(obj)	\
103 	container_of(obj, struct device_private, knode_driver)
104 #define to_device_private_bus(obj)	\
105 	container_of(obj, struct device_private, knode_bus)
106 #define to_device_private_class(obj)	\
107 	container_of(obj, struct device_private, knode_class)
108 
109 /* initialisation functions */
110 extern int devices_init(void);
111 extern int buses_init(void);
112 extern int classes_init(void);
113 extern int firmware_init(void);
114 #ifdef CONFIG_SYS_HYPERVISOR
115 extern int hypervisor_init(void);
116 #else
117 static inline int hypervisor_init(void) { return 0; }
118 #endif
119 extern int platform_bus_init(void);
120 extern void cpu_dev_init(void);
121 extern void container_dev_init(void);
122 #ifdef CONFIG_AUXILIARY_BUS
123 extern void auxiliary_bus_init(void);
124 #else
125 static inline void auxiliary_bus_init(void) { }
126 #endif
127 
128 struct kobject *virtual_device_parent(struct device *dev);
129 
130 extern int bus_add_device(struct device *dev);
131 extern void bus_probe_device(struct device *dev);
132 extern void bus_remove_device(struct device *dev);
133 
134 extern int bus_add_driver(struct device_driver *drv);
135 extern void bus_remove_driver(struct device_driver *drv);
136 extern void device_release_driver_internal(struct device *dev,
137 					   struct device_driver *drv,
138 					   struct device *parent);
139 
140 extern void driver_detach(struct device_driver *drv);
141 extern void driver_deferred_probe_del(struct device *dev);
142 extern void device_set_deferred_probe_reason(const struct device *dev,
143 					     struct va_format *vaf);
144 static inline int driver_match_device(struct device_driver *drv,
145 				      struct device *dev)
146 {
147 	return drv->bus->match ? drv->bus->match(dev, drv) : 1;
148 }
149 extern bool driver_allows_async_probing(struct device_driver *drv);
150 
151 extern int driver_add_groups(struct device_driver *drv,
152 			     const struct attribute_group **groups);
153 extern void driver_remove_groups(struct device_driver *drv,
154 				 const struct attribute_group **groups);
155 int device_driver_attach(struct device_driver *drv, struct device *dev);
156 void device_driver_detach(struct device *dev);
157 
158 extern char *make_class_name(const char *name, struct kobject *kobj);
159 
160 extern int devres_release_all(struct device *dev);
161 extern void device_block_probing(void);
162 extern void device_unblock_probing(void);
163 
164 /* /sys/devices directory */
165 extern struct kset *devices_kset;
166 extern void devices_kset_move_last(struct device *dev);
167 
168 #if defined(CONFIG_MODULES) && defined(CONFIG_SYSFS)
169 extern void module_add_driver(struct module *mod, struct device_driver *drv);
170 extern void module_remove_driver(struct device_driver *drv);
171 #else
172 static inline void module_add_driver(struct module *mod,
173 				     struct device_driver *drv) { }
174 static inline void module_remove_driver(struct device_driver *drv) { }
175 #endif
176 
177 #ifdef CONFIG_DEVTMPFS
178 extern int devtmpfs_init(void);
179 #else
180 static inline int devtmpfs_init(void) { return 0; }
181 #endif
182 
183 /* Device links support */
184 extern int device_links_read_lock(void);
185 extern void device_links_read_unlock(int idx);
186 extern int device_links_read_lock_held(void);
187 extern int device_links_check_suppliers(struct device *dev);
188 extern void device_links_force_bind(struct device *dev);
189 extern void device_links_driver_bound(struct device *dev);
190 extern void device_links_driver_cleanup(struct device *dev);
191 extern void device_links_no_driver(struct device *dev);
192 extern bool device_links_busy(struct device *dev);
193 extern void device_links_unbind_consumers(struct device *dev);
194 extern void fw_devlink_drivers_done(void);
195 
196 /* device pm support */
197 void device_pm_move_to_tail(struct device *dev);
198 
199 #ifdef CONFIG_DEVTMPFS
200 int devtmpfs_create_node(struct device *dev);
201 int devtmpfs_delete_node(struct device *dev);
202 #else
203 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
204 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
205 #endif
206