在device.h檔案中 又給提供了那些函式呢？

在這個標頭檔案中包含了 bus的一些函式 和 drifver的一些函式，以及class_create()等函式

/*原始碼**/

/*
 * device.h - generic, centralized driver model
 *
 * Copyright (c) 2001-2003 Patrick Mochel <[email protected]>
 * Copyright (c) 2004-2009 Greg Kroah-Hartman <[email protected]>
 * Copyright (c) 2008-2009 Novell Inc.
 *
 * This file is released under the GPLv2
 *
 * See Documentation/driver-model/ for more information.
 */


#ifndef _DEVICE_H_
#define _DEVICE_H_


#include <linux/ioport.h>
#include <linux/kobject.h>
#include <linux/klist.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <asm/atomic.h>
#include <asm/device.h>


struct device;
struct device_private;
struct device_driver;
struct driver_private;
struct class;
struct subsys_private;
struct bus_type;
struct device_node;


struct bus_attribute {
struct attributeattr;
ssize_t (*show)(struct bus_type *bus, char *buf);
ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
};


#define BUS_ATTR(_name, _mode, _show, _store) \
struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)


extern int __must_check bus_create_file(struct bus_type *,
struct bus_attribute *);
extern void bus_remove_file(struct bus_type *, struct bus_attribute *);


struct bus_type {
const char *name;
struct bus_attribute*bus_attrs;
struct device_attribute*dev_attrs;
struct driver_attribute*drv_attrs;


int (*match)(struct device *dev, struct device_driver *drv);
int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
int (*probe)(struct device *dev);
int (*remove)(struct device *dev);
void (*shutdown)(struct device *dev);


int (*suspend)(struct device *dev, pm_message_t state);
int (*resume)(struct device *dev);


const struct dev_pm_ops *pm;


struct subsys_private *p;
};


extern int __must_check bus_register(struct bus_type *bus);
extern void bus_unregister(struct bus_type *bus);


extern int __must_check bus_rescan_devices(struct bus_type *bus);


/* iterator helpers for buses */


int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
    int (*fn)(struct device *dev, void *data));
struct device *bus_find_device(struct bus_type *bus, struct device *start,
      void *data,
      int (*match)(struct device *dev, void *data));
struct device *bus_find_device_by_name(struct bus_type *bus,
      struct device *start,
      const char *name);


int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
    void *data, int (*fn)(struct device_driver *, void *));


void bus_sort_breadthfirst(struct bus_type *bus,
  int (*compare)(const struct device *a,
 const struct device *b));
/*
 * Bus notifiers: Get notified of addition/removal of devices
 * and binding/unbinding of drivers to devices.
 * In the long run, it should be a replacement for the platform
 * notify hooks.
 */
struct notifier_block;


extern int bus_register_notifier(struct bus_type *bus,
struct notifier_block *nb);
extern int bus_unregister_notifier(struct bus_type *bus,
  struct notifier_block *nb);


/* All 4 notifers below get called with the target struct device *
 * as an argument. Note that those functions are likely to be called
 * with the device lock held in the core, so be careful.
 */
#define BUS_NOTIFY_ADD_DEVICE0x00000001 /* device added */
#define BUS_NOTIFY_DEL_DEVICE0x00000002 /* device removed */
#define BUS_NOTIFY_BIND_DRIVER0x00000003 /* driver about to be
     bound */
#define BUS_NOTIFY_BOUND_DRIVER0x00000004 /* driver bound to device */
#define BUS_NOTIFY_UNBIND_DRIVER0x00000005 /* driver about to be
     unbound */
#define BUS_NOTIFY_UNBOUND_DRIVER0x00000006 /* driver is unbound
     from the device */


extern struct kset *bus_get_kset(struct bus_type *bus);
extern struct klist *bus_get_device_klist(struct bus_type *bus);


struct device_driver {
const char *name;
struct bus_type*bus;


struct module *owner;
const char *mod_name;/* used for built-in modules */


bool suppress_bind_attrs;/* disables bind/unbind via sysfs */


#if defined(CONFIG_OF)
const struct of_device_id*of_match_table;
#endif


int (*probe) (struct device *dev);
int (*remove) (struct device *dev);
void (*shutdown) (struct device *dev);
int (*suspend) (struct device *dev, pm_message_t state);
int (*resume) (struct device *dev);
const struct attribute_group **groups;


const struct dev_pm_ops *pm;


struct driver_private *p;
};




extern int __must_check driver_register(struct device_driver *drv);
extern void driver_unregister(struct device_driver *drv);


extern struct device_driver *get_driver(struct device_driver *drv);
extern void put_driver(struct device_driver *drv);
extern struct device_driver *driver_find(const char *name,
struct bus_type *bus);
extern int driver_probe_done(void);
extern void wait_for_device_probe(void);




/* sysfs interface for exporting driver attributes */


struct driver_attribute {
struct attribute attr;
ssize_t (*show)(struct device_driver *driver, char *buf);
ssize_t (*store)(struct device_driver *driver, const char *buf,
size_t count);
};


#define DRIVER_ATTR(_name, _mode, _show, _store) \
struct driver_attribute driver_attr_##_name = \
__ATTR(_name, _mode, _show, _store)


extern int __must_check driver_create_file(struct device_driver *driver,
const struct driver_attribute *attr);
extern void driver_remove_file(struct device_driver *driver,
      const struct driver_attribute *attr);


extern int __must_check driver_add_kobj(struct device_driver *drv,
struct kobject *kobj,
const char *fmt, ...);


extern int __must_check driver_for_each_device(struct device_driver *drv,
      struct device *start,
      void *data,
      int (*fn)(struct device *dev,
void *));
struct device *driver_find_device(struct device_driver *drv,
 struct device *start, void *data,
 int (*match)(struct device *dev, void *data));


/*
 * device classes
 */
struct class {
const char *name;
struct module *owner;


struct class_attribute*class_attrs;
struct device_attribute*dev_attrs;
struct bin_attribute*dev_bin_attrs;
struct kobject*dev_kobj;


int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
char *(*devnode)(struct device *dev, mode_t *mode);


void (*class_release)(struct class *class);
void (*dev_release)(struct device *dev);


int (*suspend)(struct device *dev, pm_message_t state);
int (*resume)(struct device *dev);


const struct kobj_ns_type_operations *ns_type;
const void *(*namespace)(struct device *dev);


const struct dev_pm_ops *pm;


struct subsys_private *p;
};


struct class_dev_iter {
struct klist_iterki;
const struct device_type*type;
};


extern struct kobject *sysfs_dev_block_kobj;
extern struct kobject *sysfs_dev_char_kobj;
extern int __must_check __class_register(struct class *class,
struct lock_class_key *key);
extern void class_unregister(struct class *class);


/* This is a #define to keep the compiler from merging different
 * instances of the __key variable */
#define class_register(class)\
({\
static struct lock_class_key __key;\
__class_register(class, &__key);\
})


struct class_compat;
struct class_compat *class_compat_register(const char *name);
void class_compat_unregister(struct class_compat *cls);
int class_compat_create_link(struct class_compat *cls, struct device *dev,
    struct device *device_link);
void class_compat_remove_link(struct class_compat *cls, struct device *dev,
     struct device *device_link);


extern void class_dev_iter_init(struct class_dev_iter *iter,
struct class *class,
struct device *start,
const struct device_type *type);
extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
extern void class_dev_iter_exit(struct class_dev_iter *iter);


extern int class_for_each_device(struct class *class, struct device *start,
void *data,
int (*fn)(struct device *dev, void *data));
extern struct device *class_find_device(struct class *class,
struct device *start, void *data,
int (*match)(struct device *, void *));


struct class_attribute {
struct attribute attr;
ssize_t (*show)(struct class *class, struct class_attribute *attr,
char *buf);
ssize_t (*store)(struct class *class, struct class_attribute *attr,
const char *buf, size_t count);
};


#define CLASS_ATTR(_name, _mode, _show, _store) \
struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)


extern int __must_check class_create_file(struct class *class,
 const struct class_attribute *attr);
extern void class_remove_file(struct class *class,
     const struct class_attribute *attr);


/* Simple class attribute that is just a static string */


struct class_attribute_string {
struct class_attribute attr;
char *str;
};


/* Currently read-only only */
#define _CLASS_ATTR_STRING(_name, _mode, _str) \
{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
#define CLASS_ATTR_STRING(_name, _mode, _str) \
struct class_attribute_string class_attr_##_name = \
_CLASS_ATTR_STRING(_name, _mode, _str)


extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
                        char *buf);


struct class_interface {
struct list_headnode;
struct class *class;


int (*add_dev)(struct device *, struct class_interface *);
void (*remove_dev)(struct device *, struct class_interface *);
};


extern int __must_check class_interface_register(struct class_interface *);
extern void class_interface_unregister(struct class_interface *);


extern struct class * __must_check __class_create(struct module *owner,
 const char *name,
 struct lock_class_key *key);
extern void class_destroy(struct class *cls);


/* This is a #define to keep the compiler from merging different
 * instances of the __key variable */
#define class_create(owner, name)\
({\
static struct lock_class_key __key;\
__class_create(owner, name, &__key);\
})


/*
 * The type of device, "struct device" is embedded in. A class
 * or bus can contain devices of different types
 * like "partitions" and "disks", "mouse" and "event".
 * This identifies the device type and carries type-specific
 * information, equivalent to the kobj_type of a kobject.
 * If "name" is specified, the uevent will contain it in
 * the DEVTYPE variable.
 */
struct device_type {
const char *name;
const struct attribute_group **groups;
int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
char *(*devnode)(struct device *dev, mode_t *mode);
void (*release)(struct device *dev);


const struct dev_pm_ops *pm;
};


/* interface for exporting device attributes */
struct device_attribute {
struct attributeattr;
ssize_t (*show)(struct device *dev, struct device_attribute *attr,
char *buf);
ssize_t (*store)(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count);
};


#define DEVICE_ATTR(_name, _mode, _show, _store) \
struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)


extern int __must_check device_create_file(struct device *device,
const struct device_attribute *entry);
extern void device_remove_file(struct device *dev,
      const struct device_attribute *attr);
extern int __must_check device_create_bin_file(struct device *dev,
const struct bin_attribute *attr);
extern void device_remove_bin_file(struct device *dev,
  const struct bin_attribute *attr);
extern int device_schedule_callback_owner(struct device *dev,
void (*func)(struct device *dev), struct module *owner);


/* This is a macro to avoid include problems with THIS_MODULE */
#define device_schedule_callback(dev, func) \
device_schedule_callback_owner(dev, func, THIS_MODULE)


/* device resource management */
typedef void (*dr_release_t)(struct device *dev, void *res);
typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);


#ifdef CONFIG_DEBUG_DEVRES
extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
    const char *name);
#define devres_alloc(release, size, gfp) \
__devres_alloc(release, size, gfp, #release)
#else
extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
#endif
extern void devres_free(void *res);
extern void devres_add(struct device *dev, void *res);
extern void *devres_find(struct device *dev, dr_release_t release,
dr_match_t match, void *match_data);
extern void *devres_get(struct device *dev, void *new_res,
dr_match_t match, void *match_data);
extern void *devres_remove(struct device *dev, dr_release_t release,
  dr_match_t match, void *match_data);
extern int devres_destroy(struct device *dev, dr_release_t release,
 dr_match_t match, void *match_data);


/* devres group */
extern void * __must_check devres_open_group(struct device *dev, void *id,
    gfp_t gfp);
extern void devres_close_group(struct device *dev, void *id);
extern void devres_remove_group(struct device *dev, void *id);
extern int devres_release_group(struct device *dev, void *id);


/* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
extern void devm_kfree(struct device *dev, void *p);


struct device_dma_parameters {
/*
* a low level driver may set these to teach IOMMU code about
* sg limitations.
*/
unsigned int max_segment_size;
unsigned long segment_boundary_mask;
};


struct device {
struct device *parent;


struct device_private*p;


struct kobject kobj;
const char *init_name; /* initial name of the device */
struct device_type*type;


struct mutex mutex;/* mutex to synchronize calls to
* its driver.
*/


struct bus_type*bus;/* type of bus device is on */
struct device_driver *driver;/* which driver has allocated this
  device */
void*platform_data;/* Platform specific data, device
  core doesn't touch it */
struct dev_pm_infopower;


#ifdef CONFIG_NUMA
intnuma_node;/* NUMA node this device is close to */
#endif
u64*dma_mask;/* dma mask (if dma'able device) */
u64coherent_dma_mask;/* Like dma_mask, but for
    alloc_coherent mappings as
    not all hardware supports
    64 bit addresses for consistent
    allocations such descriptors. */


struct device_dma_parameters *dma_parms;


struct list_headdma_pools;/* dma pools (if dma'ble) */


struct dma_coherent_mem*dma_mem; /* internal for coherent mem
    override */
/* arch specific additions */
struct dev_archdataarchdata;
#ifdef CONFIG_OF
struct device_node*of_node;
#endif


dev_tdevt;/* dev_t, creates the sysfs "dev" */


spinlock_t devres_lock;
struct list_headdevres_head;


struct klist_nodeknode_class;
struct class *class;
const struct attribute_group **groups;/* optional groups */


void(*release)(struct device *dev);
};


/* Get the wakeup routines, which depend on struct device */
#include <linux/pm_wakeup.h>


static inline const char *dev_name(const struct device *dev)
{
/* Use the init name until the kobject becomes available */
if (dev->init_name)
return dev->init_name;


return kobject_name(&dev->kobj);
}


extern int dev_set_name(struct device *dev, const char *name, ...)
__attribute__((format(printf, 2, 3)));


#ifdef CONFIG_NUMA
static inline int dev_to_node(struct device *dev)
{
return dev->numa_node;
}
static inline void set_dev_node(struct device *dev, int node)
{
dev->numa_node = node;
}
#else
static inline int dev_to_node(struct device *dev)
{
return -1;
}
static inline void set_dev_node(struct device *dev, int node)
{
}
#endif


static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
{
return dev->kobj.uevent_suppress;
}


static inline void dev_set_uevent_suppress(struct device *dev, int val)
{
dev->kobj.uevent_suppress = val;
}


static inline int device_is_registered(struct device *dev)
{
return dev->kobj.state_in_sysfs;
}


static inline void device_enable_async_suspend(struct device *dev)
{
if (!dev->power.in_suspend)
dev->power.async_suspend = true;
}


static inline void device_disable_async_suspend(struct device *dev)
{
if (!dev->power.in_suspend)
dev->power.async_suspend = false;
}


static inline bool device_async_suspend_enabled(struct device *dev)
{
return !!dev->power.async_suspend;
}


static inline void device_lock(struct device *dev)
{
mutex_lock(&dev->mutex);
}


static inline int device_trylock(struct device *dev)
{
return mutex_trylock(&dev->mutex);
}


static inline void device_unlock(struct device *dev)
{
mutex_unlock(&dev->mutex);
}


void driver_init(void);


/*
 * High level routines for use by the bus drivers
 */
extern int __must_check device_register(struct device *dev);
extern void device_unregister(struct device *dev);
extern void device_initialize(struct device *dev);
extern int __must_check device_add(struct device *dev);
extern void device_del(struct device *dev);
extern int device_for_each_child(struct device *dev, void *data,
    int (*fn)(struct device *dev, void *data));
extern struct device *device_find_child(struct device *dev, void *data,
int (*match)(struct device *dev, void *data));
extern int device_rename(struct device *dev, const char *new_name);
extern int device_move(struct device *dev, struct device *new_parent,
      enum dpm_order dpm_order);
extern const char *device_get_devnode(struct device *dev,
     mode_t *mode, const char **tmp);
extern void *dev_get_drvdata(const struct device *dev);
extern void dev_set_drvdata(struct device *dev, void *data);


/*
 * Root device objects for grouping under /sys/devices
 */
extern struct device *__root_device_register(const char *name,
    struct module *owner);
static inline struct device *root_device_register(const char *name)
{
return __root_device_register(name, THIS_MODULE);
}
extern void root_device_unregister(struct device *root);


static inline void *dev_get_platdata(const struct device *dev)
{
return dev->platform_data;
}


/*
 * Manual binding of a device to driver. See drivers/base/bus.c
 * for information on use.
 */
extern int __must_check device_bind_driver(struct device *dev);
extern void device_release_driver(struct device *dev);
extern int  __must_check device_attach(struct device *dev);
extern int __must_check driver_attach(struct device_driver *drv);
extern int __must_check device_reprobe(struct device *dev);


/*
 * Easy functions for dynamically creating devices on the fly
 */
extern struct device *device_create_vargs(struct class *cls,
 struct device *parent,
 dev_t devt,
 void *drvdata,
 const char *fmt,
 va_list vargs);
extern struct device *device_create(struct class *cls, struct device *parent,
   dev_t devt, void *drvdata,
   const char *fmt, ...)
   __attribute__((format(printf, 5, 6)));
extern void device_destroy(struct class *cls, dev_t devt);


/*
 * Platform "fixup" functions - allow the platform to have their say
 * about devices and actions that the general device layer doesn't
 * know about.
 */
/* Notify platform of device discovery */
extern int (*platform_notify)(struct device *dev);


extern int (*platform_notify_remove)(struct device *dev);




/**
 * get_device - atomically increment the reference count for the device.
 *
 */
extern struct device *get_device(struct device *dev);
extern void put_device(struct device *dev);


extern void wait_for_device_probe(void);


#ifdef CONFIG_DEVTMPFS
extern int devtmpfs_create_node(struct device *dev);
extern int devtmpfs_delete_node(struct device *dev);
extern int devtmpfs_mount(const char *mntdir);
#else
static inline int devtmpfs_create_node(struct device *dev) { return 0; }
static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
#endif


/* drivers/base/power/shutdown.c */
extern void device_shutdown(void);


/* drivers/base/sys.c */
extern void sysdev_shutdown(void);


/* debugging and troubleshooting/diagnostic helpers. */
extern const char *dev_driver_string(const struct device *dev);




#ifdef CONFIG_PRINTK


extern int dev_printk(const char *level, const struct device *dev,
     const char *fmt, ...)
__attribute__ ((format (printf, 3, 4)));
extern int dev_emerg(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
extern int dev_alert(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
extern int dev_crit(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
extern int dev_err(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
extern int dev_warn(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
extern int dev_notice(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
extern int _dev_info(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));


#else


static inline int dev_printk(const char *level, const struct device *dev,
     const char *fmt, ...)
__attribute__ ((format (printf, 3, 4)));
static inline int dev_printk(const char *level, const struct device *dev,
     const char *fmt, ...)
{ return 0; }


static inline int dev_emerg(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
static inline int dev_emerg(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline int dev_crit(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
static inline int dev_crit(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline int dev_alert(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
static inline int dev_alert(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline int dev_err(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
static inline int dev_err(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline int dev_warn(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
static inline int dev_warn(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline int dev_notice(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
static inline int dev_notice(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline int _dev_info(const struct device *dev, const char *fmt, ...)
__attribute__ ((format (printf, 2, 3)));
static inline int _dev_info(const struct device *dev, const char *fmt, ...)
{ return 0; }


#endif


/*
 * Stupid hackaround for existing uses of non-printk uses dev_info
 *
 * Note that the definition of dev_info below is actually _dev_info
 * and a macro is used to avoid redefining dev_info
 */


#define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)


#if defined(DEBUG)
#define dev_dbg(dev, format, arg...)\
dev_printk(KERN_DEBUG, dev, format, ##arg)
#elif defined(CONFIG_DYNAMIC_DEBUG)
#define dev_dbg(dev, format, ...)    \
do {    \
dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
} while (0)
#else
#define dev_dbg(dev, format, arg...)\
({\
if (0) \
dev_printk(KERN_DEBUG, dev, format, ##arg);\
0;\
})
#endif


#ifdef VERBOSE_DEBUG
#define dev_vdbgdev_dbg
#else
#define dev_vdbg(dev, format, arg...)\
({\
if (0) \
dev_printk(KERN_DEBUG, dev, format, ##arg);\
0;\
})
#endif


/*
 * dev_WARN() acts like dev_printk(), but with the key difference
 * of using a WARN/WARN_ON to get the message out, including the
 * file/line information and a backtrace.
 */
#define dev_WARN(dev, format, arg...) \
WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);


/* Create alias, so I can be autoloaded. */
#define MODULE_ALIAS_CHARDEV(major,minor) \
MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
#define MODULE_ALIAS_CHARDEV_MAJOR(major) \
MODULE_ALIAS("char-major-" __stringify(major) "-*")


#ifdef CONFIG_SYSFS_DEPRECATED
extern long sysfs_deprecated;
#else
#define sysfs_deprecated 0
#endif


#endif /* _DEVICE_H_ */