xref: /openbmc/linux/drivers/base/base.h (revision 8da5b970)
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  * @dev_root: Default device to use as the parent.
31  *
32  * @glue_dirs - "glue" directory to put in-between the parent device to
33  *              avoid namespace conflicts
34  * @class - pointer back to the struct class that this structure is associated
35  *          with.
36  *
37  * This structure is the one that is the actual kobject allowing struct
38  * bus_type/class to be statically allocated safely.  Nothing outside of the
39  * driver core should ever touch these fields.
40  */
41 struct subsys_private {
42 	struct kset subsys;
43 	struct kset *devices_kset;
44 	struct list_head interfaces;
45 	struct mutex mutex;
46 
47 	struct kset *drivers_kset;
48 	struct klist klist_devices;
49 	struct klist klist_drivers;
50 	struct blocking_notifier_head bus_notifier;
51 	unsigned int drivers_autoprobe:1;
52 	const struct bus_type *bus;
53 	struct device *dev_root;
54 
55 	struct kset glue_dirs;
56 	struct class *class;
57 
58 	struct lock_class_key lock_key;
59 };
60 #define to_subsys_private(obj) container_of_const(obj, struct subsys_private, subsys.kobj)
61 
62 static inline struct subsys_private *subsys_get(struct subsys_private *sp)
63 {
64 	if (sp)
65 		kset_get(&sp->subsys);
66 	return sp;
67 }
68 
69 static inline void subsys_put(struct subsys_private *sp)
70 {
71 	if (sp)
72 		kset_put(&sp->subsys);
73 }
74 
75 struct driver_private {
76 	struct kobject kobj;
77 	struct klist klist_devices;
78 	struct klist_node knode_bus;
79 	struct module_kobject *mkobj;
80 	struct device_driver *driver;
81 };
82 #define to_driver(obj) container_of(obj, struct driver_private, kobj)
83 
84 /**
85  * struct device_private - structure to hold the private to the driver core portions of the device structure.
86  *
87  * @klist_children - klist containing all children of this device
88  * @knode_parent - node in sibling list
89  * @knode_driver - node in driver list
90  * @knode_bus - node in bus list
91  * @knode_class - node in class list
92  * @deferred_probe - entry in deferred_probe_list which is used to retry the
93  *	binding of drivers which were unable to get all the resources needed by
94  *	the device; typically because it depends on another driver getting
95  *	probed first.
96  * @async_driver - pointer to device driver awaiting probe via async_probe
97  * @device - pointer back to the struct device that this structure is
98  * associated with.
99  * @dead - This device is currently either in the process of or has been
100  *	removed from the system. Any asynchronous events scheduled for this
101  *	device should exit without taking any action.
102  *
103  * Nothing outside of the driver core should ever touch these fields.
104  */
105 struct device_private {
106 	struct klist klist_children;
107 	struct klist_node knode_parent;
108 	struct klist_node knode_driver;
109 	struct klist_node knode_bus;
110 	struct klist_node knode_class;
111 	struct list_head deferred_probe;
112 	struct device_driver *async_driver;
113 	char *deferred_probe_reason;
114 	struct device *device;
115 	u8 dead:1;
116 };
117 #define to_device_private_parent(obj)	\
118 	container_of(obj, struct device_private, knode_parent)
119 #define to_device_private_driver(obj)	\
120 	container_of(obj, struct device_private, knode_driver)
121 #define to_device_private_bus(obj)	\
122 	container_of(obj, struct device_private, knode_bus)
123 #define to_device_private_class(obj)	\
124 	container_of(obj, struct device_private, knode_class)
125 
126 /* initialisation functions */
127 int devices_init(void);
128 int buses_init(void);
129 int classes_init(void);
130 int firmware_init(void);
131 #ifdef CONFIG_SYS_HYPERVISOR
132 int hypervisor_init(void);
133 #else
134 static inline int hypervisor_init(void) { return 0; }
135 #endif
136 int platform_bus_init(void);
137 void cpu_dev_init(void);
138 void container_dev_init(void);
139 #ifdef CONFIG_AUXILIARY_BUS
140 void auxiliary_bus_init(void);
141 #else
142 static inline void auxiliary_bus_init(void) { }
143 #endif
144 
145 struct kobject *virtual_device_parent(struct device *dev);
146 
147 int bus_add_device(struct device *dev);
148 void bus_probe_device(struct device *dev);
149 void bus_remove_device(struct device *dev);
150 void bus_notify(struct device *dev, enum bus_notifier_event value);
151 bool bus_is_registered(const struct bus_type *bus);
152 
153 int bus_add_driver(struct device_driver *drv);
154 void bus_remove_driver(struct device_driver *drv);
155 void device_release_driver_internal(struct device *dev, struct device_driver *drv,
156 				    struct device *parent);
157 
158 void driver_detach(struct device_driver *drv);
159 void driver_deferred_probe_del(struct device *dev);
160 void device_set_deferred_probe_reason(const struct device *dev, struct va_format *vaf);
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 static inline void dev_sync_state(struct device *dev)
168 {
169 	if (dev->bus->sync_state)
170 		dev->bus->sync_state(dev);
171 	else if (dev->driver && dev->driver->sync_state)
172 		dev->driver->sync_state(dev);
173 }
174 
175 int driver_add_groups(struct device_driver *drv, const struct attribute_group **groups);
176 void driver_remove_groups(struct device_driver *drv, const struct attribute_group **groups);
177 void device_driver_detach(struct device *dev);
178 
179 int devres_release_all(struct device *dev);
180 void device_block_probing(void);
181 void device_unblock_probing(void);
182 void deferred_probe_extend_timeout(void);
183 void driver_deferred_probe_trigger(void);
184 const char *device_get_devnode(const struct device *dev, umode_t *mode,
185 			       kuid_t *uid, kgid_t *gid, const char **tmp);
186 
187 /* /sys/devices directory */
188 extern struct kset *devices_kset;
189 void devices_kset_move_last(struct device *dev);
190 
191 #if defined(CONFIG_MODULES) && defined(CONFIG_SYSFS)
192 void module_add_driver(struct module *mod, struct device_driver *drv);
193 void module_remove_driver(struct device_driver *drv);
194 #else
195 static inline void module_add_driver(struct module *mod,
196 				     struct device_driver *drv) { }
197 static inline void module_remove_driver(struct device_driver *drv) { }
198 #endif
199 
200 #ifdef CONFIG_DEVTMPFS
201 int devtmpfs_init(void);
202 #else
203 static inline int devtmpfs_init(void) { return 0; }
204 #endif
205 
206 /* Device links support */
207 int device_links_read_lock(void);
208 void device_links_read_unlock(int idx);
209 int device_links_read_lock_held(void);
210 int device_links_check_suppliers(struct device *dev);
211 void device_links_force_bind(struct device *dev);
212 void device_links_driver_bound(struct device *dev);
213 void device_links_driver_cleanup(struct device *dev);
214 void device_links_no_driver(struct device *dev);
215 bool device_links_busy(struct device *dev);
216 void device_links_unbind_consumers(struct device *dev);
217 void fw_devlink_drivers_done(void);
218 void fw_devlink_probing_done(void);
219 
220 /* device pm support */
221 void device_pm_move_to_tail(struct device *dev);
222 
223 #ifdef CONFIG_DEVTMPFS
224 int devtmpfs_create_node(struct device *dev);
225 int devtmpfs_delete_node(struct device *dev);
226 #else
227 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
228 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
229 #endif
230 
231 void software_node_notify(struct device *dev);
232 void software_node_notify_remove(struct device *dev);
233