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  
subsys_get(struct subsys_private * sp)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  
subsys_put(struct subsys_private * sp)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  	const 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
hypervisor_init(void)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
auxiliary_bus_init(void)145  static inline void auxiliary_bus_init(void) { }
146  #endif
147  
148  struct kobject *virtual_device_parent(void);
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, const struct device_driver *drv,
159  				    struct device *parent);
160  
161  void driver_detach(const 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);
driver_match_device(const struct device_driver * drv,struct device * dev)164  static inline int driver_match_device(const struct device_driver *drv,
165  				      struct device *dev)
166  {
167  	return drv->bus->match ? drv->bus->match(dev, drv) : 1;
168  }
169  
dev_sync_state(struct device * dev)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(const struct device_driver *drv, const struct attribute_group **groups);
179  void driver_remove_groups(const 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, const struct device_driver *drv);
196  void module_remove_driver(const struct device_driver *drv);
197  #else
module_add_driver(struct module * mod,struct device_driver * drv)198  static inline int module_add_driver(struct module *mod,
199  				    struct device_driver *drv)
200  {
201  	return 0;
202  }
module_remove_driver(struct device_driver * drv)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
devtmpfs_init(void)209  static inline int devtmpfs_init(void) { return 0; }
210  #endif
211  
212  #ifdef CONFIG_BLOCK
213  extern const struct class block_class;
is_blockdev(struct device * dev)214  static inline bool is_blockdev(struct device *dev)
215  {
216  	return dev->class == &block_class;
217  }
218  #else
is_blockdev(struct device * dev)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
devtmpfs_create_node(struct device * dev)243  static inline int devtmpfs_create_node(struct device *dev) { return 0; }
devtmpfs_delete_node(struct device * dev)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