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 	struct lock_class_key lock_key;
57 };
58 #define to_subsys_private(obj) container_of_const(obj, struct subsys_private, subsys.kobj)
59 
subsys_get(struct subsys_private * sp)60 static inline struct subsys_private *subsys_get(struct subsys_private *sp)
61 {
62 	if (sp)
63 		kset_get(&sp->subsys);
64 	return sp;
65 }
66 
subsys_put(struct subsys_private * sp)67 static inline void subsys_put(struct subsys_private *sp)
68 {
69 	if (sp)
70 		kset_put(&sp->subsys);
71 }
72 
73 struct driver_private {
74 	struct kobject kobj;
75 	struct klist klist_devices;
76 	struct klist_node knode_bus;
77 	struct module_kobject *mkobj;
78 	struct device_driver *driver;
79 };
80 #define to_driver(obj) container_of(obj, struct driver_private, kobj)
81 
82 /**
83  * struct device_private - structure to hold the private to the driver core portions of the device structure.
84  *
85  * @klist_children - klist containing all children of this device
86  * @knode_parent - node in sibling list
87  * @knode_driver - node in driver list
88  * @knode_bus - node in bus list
89  * @knode_class - node in class list
90  * @deferred_probe - entry in deferred_probe_list which is used to retry the
91  *	binding of drivers which were unable to get all the resources needed by
92  *	the device; typically because it depends on another driver getting
93  *	probed first.
94  * @async_driver - pointer to device driver awaiting probe via async_probe
95  * @device - pointer back to the struct device that this structure is
96  * associated with.
97  * @dead - This device is currently either in the process of or has been
98  *	removed from the system. Any asynchronous events scheduled for this
99  *	device should exit without taking any action.
100  *
101  * Nothing outside of the driver core should ever touch these fields.
102  */
103 struct device_private {
104 	struct klist klist_children;
105 	struct klist_node knode_parent;
106 	struct klist_node knode_driver;
107 	struct klist_node knode_bus;
108 	struct klist_node knode_class;
109 	struct list_head deferred_probe;
110 	struct device_driver *async_driver;
111 	char *deferred_probe_reason;
112 	struct device *device;
113 	u8 dead:1;
114 };
115 #define to_device_private_parent(obj)	\
116 	container_of(obj, struct device_private, knode_parent)
117 #define to_device_private_driver(obj)	\
118 	container_of(obj, struct device_private, knode_driver)
119 #define to_device_private_bus(obj)	\
120 	container_of(obj, struct device_private, knode_bus)
121 #define to_device_private_class(obj)	\
122 	container_of(obj, struct device_private, knode_class)
123 
124 /* initialisation functions */
125 extern int devices_init(void);
126 extern int buses_init(void);
127 extern int classes_init(void);
128 extern int firmware_init(void);
129 #ifdef CONFIG_SYS_HYPERVISOR
130 extern int hypervisor_init(void);
131 #else
hypervisor_init(void)132 static inline int hypervisor_init(void) { return 0; }
133 #endif
134 extern int platform_bus_init(void);
135 extern void cpu_dev_init(void);
136 extern void container_dev_init(void);
137 #ifdef CONFIG_AUXILIARY_BUS
138 extern void auxiliary_bus_init(void);
139 #else
auxiliary_bus_init(void)140 static inline void auxiliary_bus_init(void) { }
141 #endif
142 
143 struct kobject *virtual_device_parent(struct device *dev);
144 
145 extern int bus_add_device(struct device *dev);
146 extern void bus_probe_device(struct device *dev);
147 extern void bus_remove_device(struct device *dev);
148 void bus_notify(struct device *dev, enum bus_notifier_event value);
149 bool bus_is_registered(const struct bus_type *bus);
150 
151 extern int bus_add_driver(struct device_driver *drv);
152 extern void bus_remove_driver(struct device_driver *drv);
153 extern void device_release_driver_internal(struct device *dev,
154 					   struct device_driver *drv,
155 					   struct device *parent);
156 
157 extern void driver_detach(struct device_driver *drv);
158 extern void driver_deferred_probe_del(struct device *dev);
159 extern void device_set_deferred_probe_reason(const struct device *dev,
160 					     struct va_format *vaf);
driver_match_device(struct device_driver * drv,struct device * dev)161 static inline int driver_match_device(struct device_driver *drv,
162 				      struct device *dev)
163 {
164 	return drv->bus->match ? drv->bus->match(dev, drv) : 1;
165 }
166 
167 extern int driver_add_groups(struct device_driver *drv,
168 			     const struct attribute_group **groups);
169 extern void driver_remove_groups(struct device_driver *drv,
170 				 const struct attribute_group **groups);
171 void device_driver_detach(struct device *dev);
172 
173 extern int devres_release_all(struct device *dev);
174 extern void device_block_probing(void);
175 extern void device_unblock_probing(void);
176 extern void deferred_probe_extend_timeout(void);
177 extern void driver_deferred_probe_trigger(void);
178 const char *device_get_devnode(const struct device *dev, umode_t *mode,
179 			       kuid_t *uid, kgid_t *gid, const char **tmp);
180 
181 /* /sys/devices directory */
182 extern struct kset *devices_kset;
183 extern void devices_kset_move_last(struct device *dev);
184 
185 #if defined(CONFIG_MODULES) && defined(CONFIG_SYSFS)
186 extern void module_add_driver(struct module *mod, struct device_driver *drv);
187 extern void module_remove_driver(struct device_driver *drv);
188 #else
module_add_driver(struct module * mod,struct device_driver * drv)189 static inline void module_add_driver(struct module *mod,
190 				     struct device_driver *drv) { }
module_remove_driver(struct device_driver * drv)191 static inline void module_remove_driver(struct device_driver *drv) { }
192 #endif
193 
194 #ifdef CONFIG_DEVTMPFS
195 extern int devtmpfs_init(void);
196 #else
devtmpfs_init(void)197 static inline int devtmpfs_init(void) { return 0; }
198 #endif
199 
200 /* Device links support */
201 extern int device_links_read_lock(void);
202 extern void device_links_read_unlock(int idx);
203 extern int device_links_read_lock_held(void);
204 extern int device_links_check_suppliers(struct device *dev);
205 extern void device_links_force_bind(struct device *dev);
206 extern void device_links_driver_bound(struct device *dev);
207 extern void device_links_driver_cleanup(struct device *dev);
208 extern void device_links_no_driver(struct device *dev);
209 extern bool device_links_busy(struct device *dev);
210 extern void device_links_unbind_consumers(struct device *dev);
211 extern void fw_devlink_drivers_done(void);
212 
213 /* device pm support */
214 void device_pm_move_to_tail(struct device *dev);
215 
216 #ifdef CONFIG_DEVTMPFS
217 int devtmpfs_create_node(struct device *dev);
218 int devtmpfs_delete_node(struct device *dev);
219 #else
devtmpfs_create_node(struct device * dev)220 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
devtmpfs_delete_node(struct device * dev)221 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
222 #endif
223 
224 void software_node_notify(struct device *dev);
225 void software_node_notify_remove(struct device *dev);
226