xref: /openbmc/linux/drivers/base/base.h (revision 93696d8f)
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  * @lock_key:	Lock class key for use by the lock validator
37  *
38  * This structure is the one that is the actual kobject allowing struct
39  * bus_type/class to be statically allocated safely.  Nothing outside of the
40  * driver core should ever touch these fields.
41  */
42 struct subsys_private {
43 	struct kset subsys;
44 	struct kset *devices_kset;
45 	struct list_head interfaces;
46 	struct mutex mutex;
47 
48 	struct kset *drivers_kset;
49 	struct klist klist_devices;
50 	struct klist klist_drivers;
51 	struct blocking_notifier_head bus_notifier;
52 	unsigned int drivers_autoprobe:1;
53 	const struct bus_type *bus;
54 	struct device *dev_root;
55 
56 	struct kset glue_dirs;
57 	const struct class *class;
58 
59 	struct lock_class_key lock_key;
60 };
61 #define to_subsys_private(obj) container_of_const(obj, struct subsys_private, subsys.kobj)
62 
63 static inline struct subsys_private *subsys_get(struct subsys_private *sp)
64 {
65 	if (sp)
66 		kset_get(&sp->subsys);
67 	return sp;
68 }
69 
70 static inline void subsys_put(struct subsys_private *sp)
71 {
72 	if (sp)
73 		kset_put(&sp->subsys);
74 }
75 
76 struct subsys_private *class_to_subsys(const struct class *class);
77 
78 struct driver_private {
79 	struct kobject kobj;
80 	struct klist klist_devices;
81 	struct klist_node knode_bus;
82 	struct module_kobject *mkobj;
83 	struct device_driver *driver;
84 };
85 #define to_driver(obj) container_of(obj, struct driver_private, kobj)
86 
87 /**
88  * struct device_private - structure to hold the private to the driver core portions of the device structure.
89  *
90  * @klist_children - klist containing all children of this device
91  * @knode_parent - node in sibling list
92  * @knode_driver - node in driver list
93  * @knode_bus - node in bus list
94  * @knode_class - node in class list
95  * @deferred_probe - entry in deferred_probe_list which is used to retry the
96  *	binding of drivers which were unable to get all the resources needed by
97  *	the device; typically because it depends on another driver getting
98  *	probed first.
99  * @async_driver - pointer to device driver awaiting probe via async_probe
100  * @device - pointer back to the struct device that this structure is
101  * associated with.
102  * @dead - This device is currently either in the process of or has been
103  *	removed from the system. Any asynchronous events scheduled for this
104  *	device should exit without taking any action.
105  *
106  * Nothing outside of the driver core should ever touch these fields.
107  */
108 struct device_private {
109 	struct klist klist_children;
110 	struct klist_node knode_parent;
111 	struct klist_node knode_driver;
112 	struct klist_node knode_bus;
113 	struct klist_node knode_class;
114 	struct list_head deferred_probe;
115 	struct device_driver *async_driver;
116 	char *deferred_probe_reason;
117 	struct device *device;
118 	u8 dead:1;
119 };
120 #define to_device_private_parent(obj)	\
121 	container_of(obj, struct device_private, knode_parent)
122 #define to_device_private_driver(obj)	\
123 	container_of(obj, struct device_private, knode_driver)
124 #define to_device_private_bus(obj)	\
125 	container_of(obj, struct device_private, knode_bus)
126 #define to_device_private_class(obj)	\
127 	container_of(obj, struct device_private, knode_class)
128 
129 /* initialisation functions */
130 int devices_init(void);
131 int buses_init(void);
132 int classes_init(void);
133 int firmware_init(void);
134 #ifdef CONFIG_SYS_HYPERVISOR
135 int hypervisor_init(void);
136 #else
137 static inline int hypervisor_init(void) { return 0; }
138 #endif
139 int platform_bus_init(void);
140 void cpu_dev_init(void);
141 void container_dev_init(void);
142 #ifdef CONFIG_AUXILIARY_BUS
143 void auxiliary_bus_init(void);
144 #else
145 static inline void auxiliary_bus_init(void) { }
146 #endif
147 
148 struct kobject *virtual_device_parent(struct device *dev);
149 
150 int bus_add_device(struct device *dev);
151 void bus_probe_device(struct device *dev);
152 void bus_remove_device(struct device *dev);
153 void bus_notify(struct device *dev, enum bus_notifier_event value);
154 bool bus_is_registered(const struct bus_type *bus);
155 
156 int bus_add_driver(struct device_driver *drv);
157 void bus_remove_driver(struct device_driver *drv);
158 void device_release_driver_internal(struct device *dev, struct device_driver *drv,
159 				    struct device *parent);
160 
161 void driver_detach(struct device_driver *drv);
162 void driver_deferred_probe_del(struct device *dev);
163 void device_set_deferred_probe_reason(const struct device *dev, struct va_format *vaf);
164 static inline int driver_match_device(struct device_driver *drv,
165 				      struct device *dev)
166 {
167 	return drv->bus->match ? drv->bus->match(dev, drv) : 1;
168 }
169 
170 static inline void dev_sync_state(struct device *dev)
171 {
172 	if (dev->bus->sync_state)
173 		dev->bus->sync_state(dev);
174 	else if (dev->driver && dev->driver->sync_state)
175 		dev->driver->sync_state(dev);
176 }
177 
178 int driver_add_groups(struct device_driver *drv, const struct attribute_group **groups);
179 void driver_remove_groups(struct device_driver *drv, const struct attribute_group **groups);
180 void device_driver_detach(struct device *dev);
181 
182 int devres_release_all(struct device *dev);
183 void device_block_probing(void);
184 void device_unblock_probing(void);
185 void deferred_probe_extend_timeout(void);
186 void driver_deferred_probe_trigger(void);
187 const char *device_get_devnode(const struct device *dev, umode_t *mode,
188 			       kuid_t *uid, kgid_t *gid, const char **tmp);
189 
190 /* /sys/devices directory */
191 extern struct kset *devices_kset;
192 void devices_kset_move_last(struct device *dev);
193 
194 #if defined(CONFIG_MODULES) && defined(CONFIG_SYSFS)
195 int module_add_driver(struct module *mod, struct device_driver *drv);
196 void module_remove_driver(struct device_driver *drv);
197 #else
198 static inline int module_add_driver(struct module *mod,
199 				    struct device_driver *drv)
200 {
201 	return 0;
202 }
203 static inline void module_remove_driver(struct device_driver *drv) { }
204 #endif
205 
206 #ifdef CONFIG_DEVTMPFS
207 int devtmpfs_init(void);
208 #else
209 static inline int devtmpfs_init(void) { return 0; }
210 #endif
211 
212 #ifdef CONFIG_BLOCK
213 extern struct class block_class;
214 static inline bool is_blockdev(struct device *dev)
215 {
216 	return dev->class == &block_class;
217 }
218 #else
219 static inline bool is_blockdev(struct device *dev) { return false; }
220 #endif
221 
222 /* Device links support */
223 int device_links_read_lock(void);
224 void device_links_read_unlock(int idx);
225 int device_links_read_lock_held(void);
226 int device_links_check_suppliers(struct device *dev);
227 void device_links_force_bind(struct device *dev);
228 void device_links_driver_bound(struct device *dev);
229 void device_links_driver_cleanup(struct device *dev);
230 void device_links_no_driver(struct device *dev);
231 bool device_links_busy(struct device *dev);
232 void device_links_unbind_consumers(struct device *dev);
233 void fw_devlink_drivers_done(void);
234 void fw_devlink_probing_done(void);
235 
236 /* device pm support */
237 void device_pm_move_to_tail(struct device *dev);
238 
239 #ifdef CONFIG_DEVTMPFS
240 int devtmpfs_create_node(struct device *dev);
241 int devtmpfs_delete_node(struct device *dev);
242 #else
243 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
244 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
245 #endif
246 
247 void software_node_notify(struct device *dev);
248 void software_node_notify_remove(struct device *dev);
249