device.h

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/*
 * 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/mutex.h>
#include <linux/pm.h>
#include <linux/atomic.h>
#include <linux/ratelimit.h>
#include <asm/device.h>

struct device;
struct device_private;
struct device_driver;
struct driver_private;
struct module;
struct class;
struct subsys_private;
struct bus_type;
struct device_node;
struct iommu_ops;
struct iommu_group;

struct bus_attribute {
    struct attribute    attr;
    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;
    const char      *dev_name;
    struct device       *dev_root;
    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 iommu_ops *iommu_ops;

    struct subsys_private *p;
};

/* This is a #define to keep the compiler from merging different
 * instances of the __key variable */
#define bus_register(subsys)            \
({                      \
    static struct lock_class_key __key; \
    __bus_register(subsys, &__key); \
})
extern int __must_check __bus_register(struct bus_type *bus,
                       struct lock_class_key *key);
extern void bus_unregister(struct bus_type *bus);

extern int __must_check bus_rescan_devices(struct bus_type *bus);

/* iterator helpers for buses */
struct subsys_dev_iter {
    struct klist_iter       ki;
    const struct device_type    *type;
};
void subsys_dev_iter_init(struct subsys_dev_iter *iter,
             struct bus_type *subsys,
             struct device *start,
             const struct device_type *type);
struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
void subsys_dev_iter_exit(struct subsys_dev_iter *iter);

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);
struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
                    struct device *hint);
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_DEVICE       0x00000001 /* device added */
#define BUS_NOTIFY_DEL_DEVICE       0x00000002 /* device removed */
#define BUS_NOTIFY_BIND_DRIVER      0x00000003 /* driver about to be
                              bound */
#define BUS_NOTIFY_BOUND_DRIVER     0x00000004 /* driver bound to device */
#define BUS_NOTIFY_UNBIND_DRIVER    0x00000005 /* driver about to be
                              unbound */
#define BUS_NOTIFY_UNBOUND_DRIVER   0x00000006 /* 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 */

    const struct of_device_id   *of_match_table;

    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 *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_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));

struct subsys_interface {
    const char *name;
    struct bus_type *subsys;
    struct list_head node;
    int (*add_dev)(struct device *dev, struct subsys_interface *sif);
    int (*remove_dev)(struct device *dev, struct subsys_interface *sif);
};

int subsys_interface_register(struct subsys_interface *sif);
void subsys_interface_unregister(struct subsys_interface *sif);

int subsys_system_register(struct bus_type *subsys,
               const struct attribute_group **groups);

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, umode_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_iter       ki;
    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);
    const void *(*namespace)(struct class *class,
                 const struct class_attribute *attr);
};

#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_head    node;
    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, umode_t *mode);
    void (*release)(struct device *dev);

    const struct dev_pm_ops *pm;
};

/* interface for exporting device attributes */
struct device_attribute {
    struct attribute    attr;
    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);
};

struct dev_ext_attribute {
    struct device_attribute attr;
    void *var;
};

ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
              char *buf);
ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
               const char *buf, size_t count);
ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
            char *buf);
ssize_t device_store_int(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)
#define DEVICE_ULONG_ATTR(_name, _mode, _var) \
    struct dev_ext_attribute dev_attr_##_name = \
        { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
#define DEVICE_INT_ATTR(_name, _mode, _var) \
    struct dev_ext_attribute dev_attr_##_name = \
        { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
#define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
    struct device_attribute dev_attr_##_name =      \
        __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)

extern int 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_for_each_res(struct device *dev, dr_release_t release,
                dr_match_t match, void *match_data,
                void (*fn)(struct device *, void *, void *),
                void *data);
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);
extern int devres_release(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);

void __iomem *devm_request_and_ioremap(struct device *dev,
            struct resource *res);

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 */
    const 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_info  power;
    struct dev_pm_domain    *pm_domain;

#ifdef CONFIG_NUMA
    int     numa_node;  /* NUMA node this device is close to */
#endif
    u64     *dma_mask;  /* dma mask (if dma'able device) */
    u64     coherent_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_head    dma_pools;  /* dma pools (if dma'ble) */

    struct dma_coherent_mem *dma_mem; /* internal for coherent mem
                         override */
#ifdef CONFIG_CMA
    struct cma *cma_area;       /* contiguous memory area for dma
                       allocations */
#endif
    /* arch specific additions */
    struct dev_archdata archdata;

    struct device_node  *of_node; /* associated device tree node */

    dev_t           devt;   /* dev_t, creates the sysfs "dev" */
    u32         id; /* device instance */

    spinlock_t      devres_lock;
    struct list_head    devres_head;

    struct klist_node   knode_class;
    struct class        *class;
    const struct attribute_group **groups;  /* optional groups */

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

static inline struct device *kobj_to_dev(struct kobject *kobj)
{
    return container_of(kobj, struct device, kobj);
}

/* 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 __printf(2, 3)
int dev_set_name(struct device *dev, const char *name, ...);

#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 struct pm_subsys_data *dev_to_psd(struct device *dev)
{
    return dev ? dev->power.subsys_data : NULL;
}

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.is_prepared)
        dev->power.async_suspend = true;
}

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

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

static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
{
    dev->power.ignore_children = enable;
}

static inline void dev_pm_syscore_device(struct device *dev, bool val)
{
#ifdef CONFIG_PM_SLEEP
    dev->power.syscore = val;
#endif
}

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,
                      umode_t *mode, const char **tmp);
extern void *dev_get_drvdata(const struct device *dev);
extern int 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);

/*
 * This is a macro to avoid include problems with THIS_MODULE,
 * just as per what is done for device_schedule_callback() above.
 */
#define root_device_register(name) \
    __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 __printf(5, 6)
struct device *device_create(struct class *cls, struct device *parent,
                 dev_t devt, void *drvdata,
                 const char *fmt, ...);
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);

#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);

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


#ifdef CONFIG_PRINTK

extern __printf(3, 0)
int dev_vprintk_emit(int level, const struct device *dev,
             const char *fmt, va_list args);
extern __printf(3, 4)
int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);

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

#else

static inline __printf(3, 0)
int dev_vprintk_emit(int level, const struct device *dev,
             const char *fmt, va_list args)
{ return 0; }
static inline __printf(3, 4)
int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
{ return 0; }

static inline int __dev_printk(const char *level, const struct device *dev,
                   struct va_format *vaf)
{ return 0; }
static inline __printf(3, 4)
int dev_printk(const char *level, const struct device *dev,
           const char *fmt, ...)
{ return 0; }

static inline __printf(2, 3)
int dev_emerg(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline __printf(2, 3)
int dev_crit(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline __printf(2, 3)
int dev_alert(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline __printf(2, 3)
int dev_err(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline __printf(2, 3)
int dev_warn(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline __printf(2, 3)
int dev_notice(const struct device *dev, const char *fmt, ...)
{ return 0; }
static inline __printf(2, 3)
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(CONFIG_DYNAMIC_DEBUG)
#define dev_dbg(dev, format, ...)            \
do {                             \
    dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
} while (0)
#elif defined(DEBUG)
#define dev_dbg(dev, format, arg...)        \
    dev_printk(KERN_DEBUG, dev, format, ##arg)
#else
#define dev_dbg(dev, format, arg...)                \
({                              \
    if (0)                          \
        dev_printk(KERN_DEBUG, dev, format, ##arg); \
    0;                          \
})
#endif

#define dev_level_ratelimited(dev_level, dev, fmt, ...)         \
do {                                    \
    static DEFINE_RATELIMIT_STATE(_rs,              \
                      DEFAULT_RATELIMIT_INTERVAL,   \
                      DEFAULT_RATELIMIT_BURST);     \
    if (__ratelimit(&_rs))                      \
        dev_level(dev, fmt, ##__VA_ARGS__);         \
} while (0)

#define dev_emerg_ratelimited(dev, fmt, ...)                \
    dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
#define dev_alert_ratelimited(dev, fmt, ...)                \
    dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
#define dev_crit_ratelimited(dev, fmt, ...)             \
    dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
#define dev_err_ratelimited(dev, fmt, ...)              \
    dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
#define dev_warn_ratelimited(dev, fmt, ...)             \
    dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
#define dev_notice_ratelimited(dev, fmt, ...)               \
    dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
#define dev_info_ratelimited(dev, fmt, ...)             \
    dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
#if defined(CONFIG_DYNAMIC_DEBUG) || defined(DEBUG)
#define dev_dbg_ratelimited(dev, fmt, ...)              \
do {                                    \
    static DEFINE_RATELIMIT_STATE(_rs,              \
                      DEFAULT_RATELIMIT_INTERVAL,   \
                      DEFAULT_RATELIMIT_BURST);     \
    DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);         \
    if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&    \
        __ratelimit(&_rs))                      \
        __dynamic_pr_debug(&descriptor, pr_fmt(fmt),        \
                   ##__VA_ARGS__);          \
} while (0)
#else
#define dev_dbg_ratelimited(dev, fmt, ...)          \
    no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#endif

#ifdef VERBOSE_DEBUG
#define dev_vdbg    dev_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);

#define dev_WARN_ONCE(dev, condition, format, arg...) \
    WARN_ONCE(condition, "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

#define module_driver(__driver, __register, __unregister, ...) \
static int __init __driver##_init(void) \
{ \
    return __register(&(__driver) , ##__VA_ARGS__); \
} \
module_init(__driver##_init); \
static void __exit __driver##_exit(void) \
{ \
    __unregister(&(__driver) , ##__VA_ARGS__); \
} \
module_exit(__driver##_exit);

#endif /* _DEVICE_H_ */