Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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
17 * portions of the bus_type/class structure.
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 * @drivers_kset: the list of drivers associated
23 * @klist_devices: the klist to iterate over the @devices_kset
24 * @klist_drivers: the klist to iterate over the @drivers_kset
25 * @bus_notifier: the bus notifier list for anything that cares about things
26 * on this bus.
27 * @drivers_autoprobe: gate whether new devices are automatically attached to
28 * registered drivers, or new drivers automatically attach
29 * to existing devices.
30 * @bus: pointer back to the struct bus_type that this structure is associated
31 * with.
32 * @dev_root: Default device to use as the parent.
33 * @glue_dirs: "glue" directory to put in-between the parent device to
34 * avoid namespace conflicts
35 * @class: pointer back to the struct class that this structure is associated
36 * with.
37 * @lock_key: Lock class key for use by the lock validator
38 *
39 * This structure is the one that is the actual kobject allowing struct
40 * bus_type/class to be statically allocated safely. Nothing outside of the
41 * driver core should ever touch these fields.
42 */
43struct subsys_private {
44 struct kset subsys;
45 struct kset *devices_kset;
46 struct list_head interfaces;
47 struct mutex mutex;
48
49 struct kset *drivers_kset;
50 struct klist klist_devices;
51 struct klist klist_drivers;
52 struct blocking_notifier_head bus_notifier;
53 unsigned int drivers_autoprobe:1;
54 const struct bus_type *bus;
55 struct device *dev_root;
56
57 struct kset glue_dirs;
58 const struct class *class;
59
60 struct lock_class_key lock_key;
61};
62#define to_subsys_private(obj) container_of_const(obj, struct subsys_private, subsys.kobj)
63
64static inline struct subsys_private *subsys_get(struct subsys_private *sp)
65{
66 if (sp)
67 kset_get(&sp->subsys);
68 return sp;
69}
70
71static inline void subsys_put(struct subsys_private *sp)
72{
73 if (sp)
74 kset_put(&sp->subsys);
75}
76
77struct subsys_private *bus_to_subsys(const struct bus_type *bus);
78struct subsys_private *class_to_subsys(const struct class *class);
79
80struct driver_private {
81 struct kobject kobj;
82 struct klist klist_devices;
83 struct klist_node knode_bus;
84 struct module_kobject *mkobj;
85 struct device_driver *driver;
86};
87#define to_driver(obj) container_of(obj, struct driver_private, kobj)
88
89#ifdef CONFIG_RUST
90/**
91 * struct driver_type - Representation of a Rust driver type.
92 */
93struct driver_type {
94 /**
95 * @id: Representation of core::any::TypeId.
96 */
97 u8 id[16];
98} __packed;
99#endif
100
101/**
102 * struct device_private - structure to hold the private to the driver core
103 * portions of the device structure.
104 * @klist_children: klist containing all children of this device
105 * @knode_parent: node in sibling list
106 * @knode_driver: node in driver list
107 * @knode_bus: node in bus list
108 * @knode_class: node in class list
109 * @deferred_probe: entry in deferred_probe_list which is used to retry the
110 * binding of drivers which were unable to get all the
111 * resources needed by the device; typically because it depends
112 * on another driver getting probed first.
113 * @async_driver: pointer to device driver awaiting probe via async_probe
114 * @deferred_probe_reason: capture the -EPROBE_DEFER message emitted with
115 * dev_err_probe() for later retrieval via debugfs
116 * @device: pointer back to the struct device that this structure is
117 * associated with.
118 * @driver_type: The type of the bound Rust driver.
119 * @dead: This device is currently either in the process of or has been
120 * removed from the system. Any asynchronous events scheduled for this
121 * device should exit without taking any action.
122 *
123 * Nothing outside of the driver core should ever touch these fields.
124 */
125struct device_private {
126 struct klist klist_children;
127 struct klist_node knode_parent;
128 struct klist_node knode_driver;
129 struct klist_node knode_bus;
130 struct klist_node knode_class;
131 struct list_head deferred_probe;
132 const struct device_driver *async_driver;
133 char *deferred_probe_reason;
134 struct device *device;
135#ifdef CONFIG_RUST
136 struct driver_type driver_type;
137#endif
138 u8 dead:1;
139};
140#define to_device_private_parent(obj) \
141 container_of(obj, struct device_private, knode_parent)
142#define to_device_private_driver(obj) \
143 container_of(obj, struct device_private, knode_driver)
144#define to_device_private_bus(obj) \
145 container_of(obj, struct device_private, knode_bus)
146#define to_device_private_class(obj) \
147 container_of(obj, struct device_private, knode_class)
148
149/* initialisation functions */
150int devices_init(void);
151int buses_init(void);
152int classes_init(void);
153int firmware_init(void);
154#ifdef CONFIG_SYS_HYPERVISOR
155int hypervisor_init(void);
156#else
157static inline int hypervisor_init(void) { return 0; }
158#endif
159int platform_bus_init(void);
160int faux_bus_init(void);
161void cpu_dev_init(void);
162void container_dev_init(void);
163#ifdef CONFIG_AUXILIARY_BUS
164void auxiliary_bus_init(void);
165#else
166static inline void auxiliary_bus_init(void) { }
167#endif
168
169struct kobject *virtual_device_parent(void);
170
171int bus_add_device(struct device *dev);
172void bus_probe_device(struct device *dev);
173void bus_remove_device(struct device *dev);
174void bus_notify(struct device *dev, enum bus_notifier_event value);
175bool bus_is_registered(const struct bus_type *bus);
176
177int bus_add_driver(struct device_driver *drv);
178void bus_remove_driver(struct device_driver *drv);
179void device_release_driver_internal(struct device *dev, const struct device_driver *drv,
180 struct device *parent);
181
182void driver_detach(const struct device_driver *drv);
183void driver_deferred_probe_del(struct device *dev);
184void device_set_deferred_probe_reason(const struct device *dev, struct va_format *vaf);
185static inline int driver_match_device(const struct device_driver *drv,
186 struct device *dev)
187{
188 return drv->bus->match ? drv->bus->match(dev, drv) : 1;
189}
190
191static inline void dev_sync_state(struct device *dev)
192{
193 if (dev->bus->sync_state)
194 dev->bus->sync_state(dev);
195 else if (dev->driver && dev->driver->sync_state)
196 dev->driver->sync_state(dev);
197}
198
199int driver_add_groups(const struct device_driver *drv, const struct attribute_group **groups);
200void driver_remove_groups(const struct device_driver *drv, const struct attribute_group **groups);
201void device_driver_detach(struct device *dev);
202
203static inline void device_set_driver(struct device *dev, const struct device_driver *drv)
204{
205 /*
206 * Majority (all?) read accesses to dev->driver happens either
207 * while holding device lock or in bus/driver code that is only
208 * invoked when the device is bound to a driver and there is no
209 * concern of the pointer being changed while it is being read.
210 * However when reading device's uevent file we read driver pointer
211 * without taking device lock (so we do not block there for
212 * arbitrary amount of time). We use WRITE_ONCE() here to prevent
213 * tearing so that READ_ONCE() can safely be used in uevent code.
214 */
215 // FIXME - this cast should not be needed "soon"
216 WRITE_ONCE(dev->driver, (struct device_driver *)drv);
217}
218
219struct devres_node;
220typedef void (*dr_node_release_t)(struct device *dev, struct devres_node *node);
221typedef void (*dr_node_free_t)(struct devres_node *node);
222
223struct devres_node {
224 struct list_head entry;
225 dr_node_release_t release;
226 dr_node_free_t free_node;
227 const char *name;
228 size_t size;
229};
230
231void devres_node_init(struct devres_node *node, dr_node_release_t release,
232 dr_node_free_t free_node);
233void devres_node_add(struct device *dev, struct devres_node *node);
234bool devres_node_remove(struct device *dev, struct devres_node *node);
235void devres_set_node_dbginfo(struct devres_node *node, const char *name,
236 size_t size);
237void devres_for_each_res(struct device *dev, dr_release_t release,
238 dr_match_t match, void *match_data,
239 void (*fn)(struct device *, void *, void *),
240 void *data);
241int devres_release_all(struct device *dev);
242void device_block_probing(void);
243void device_unblock_probing(void);
244void deferred_probe_extend_timeout(void);
245void driver_deferred_probe_trigger(void);
246const char *device_get_devnode(const struct device *dev, umode_t *mode,
247 kuid_t *uid, kgid_t *gid, const char **tmp);
248
249/* /sys/devices directory */
250extern struct kset *devices_kset;
251void devices_kset_move_last(struct device *dev);
252
253#if defined(CONFIG_MODULES) && defined(CONFIG_SYSFS)
254int module_add_driver(struct module *mod, const struct device_driver *drv);
255void module_remove_driver(const struct device_driver *drv);
256#else
257static inline int module_add_driver(struct module *mod,
258 struct device_driver *drv)
259{
260 return 0;
261}
262static inline void module_remove_driver(struct device_driver *drv) { }
263#endif
264
265#ifdef CONFIG_DEVTMPFS
266int devtmpfs_init(void);
267#else
268static inline int devtmpfs_init(void) { return 0; }
269#endif
270
271#ifdef CONFIG_BLOCK
272extern const struct class block_class;
273static inline bool is_blockdev(struct device *dev)
274{
275 return dev->class == &block_class;
276}
277#else
278static inline bool is_blockdev(struct device *dev) { return false; }
279#endif
280
281/* Device links support */
282int device_links_read_lock(void);
283void device_links_read_unlock(int idx);
284int device_links_read_lock_held(void);
285int device_links_check_suppliers(struct device *dev);
286void device_links_force_bind(struct device *dev);
287void device_links_driver_bound(struct device *dev);
288void device_links_driver_cleanup(struct device *dev);
289void device_links_no_driver(struct device *dev);
290bool device_links_busy(struct device *dev);
291void device_links_unbind_consumers(struct device *dev);
292bool device_link_flag_is_sync_state_only(u32 flags);
293void fw_devlink_drivers_done(void);
294void fw_devlink_probing_done(void);
295
296#define dev_for_each_link_to_supplier(__link, __dev) \
297 list_for_each_entry_srcu(__link, &(__dev)->links.suppliers, c_node, \
298 device_links_read_lock_held())
299
300#define dev_for_each_link_to_consumer(__link, __dev) \
301 list_for_each_entry_srcu(__link, &(__dev)->links.consumers, s_node, \
302 device_links_read_lock_held())
303
304/* device pm support */
305void device_pm_move_to_tail(struct device *dev);
306
307#ifdef CONFIG_DEVTMPFS
308int devtmpfs_create_node(struct device *dev);
309int devtmpfs_delete_node(struct device *dev);
310#else
311static inline int devtmpfs_create_node(struct device *dev) { return 0; }
312static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
313#endif
314
315void software_node_init(void);
316void software_node_notify(struct device *dev);
317void software_node_notify_remove(struct device *dev);
318
319#ifdef CONFIG_PINCTRL
320int pinctrl_bind_pins(struct device *dev);
321#else
322static inline int pinctrl_bind_pins(struct device *dev)
323{
324 return 0;
325}
326#endif /* CONFIG_PINCTRL */