include/linux/device.h

   1 /*
   2  * device.h - generic, centralized driver model
   3  *
   4  * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
   5  * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
   6  * Copyright (c) 2008-2009 Novell Inc.
   7  *
   8  * This file is released under the GPLv2
   9  *
  10  * See Documentation/driver-model/ for more information.
  11  */
  12
  13 #ifndef _DEVICE_H_
  14 #define _DEVICE_H_
  15
  16 #include <linux/ioport.h>
  17 #include <linux/kobject.h>
  18 #include <linux/klist.h>
  19 #include <linux/list.h>
  20 #include <linux/lockdep.h>
  21 #include <linux/compiler.h>
  22 #include <linux/types.h>
  23 #include <linux/module.h>
  24 #include <linux/pm.h>
  25 #include <asm/atomic.h>
  26 #include <asm/device.h>
  27
  28 struct device;
  29 struct device_private;
  30 struct device_driver;
  31 struct driver_private;
  32 struct class;
  33 struct class_private;
  34 struct bus_type;
  35 struct bus_type_private;
  36
  37 struct bus_attribute {
  38         struct attribute        attr;
  39         ssize_t (*show)(struct bus_type *bus, char *buf);
  40         ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
  41 };
  42
  43 #define BUS_ATTR(_name, _mode, _show, _store)   \
  44 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
  45
  46 extern int __must_check bus_create_file(struct bus_type *,
  47                                         struct bus_attribute *);
  48 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
  49
  50 struct bus_type {
  51         const char              *name;
  52         struct bus_attribute    *bus_attrs;
  53         struct device_attribute *dev_attrs;
  54         struct driver_attribute *drv_attrs;
  55
  56         int (*match)(struct device *dev, struct device_driver *drv);
  57         int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
  58         int (*probe)(struct device *dev);
  59         int (*remove)(struct device *dev);
  60         void (*shutdown)(struct device *dev);
  61
  62         int (*suspend)(struct device *dev, pm_message_t state);
  63         int (*resume)(struct device *dev);
  64
  65         const struct dev_pm_ops *pm;
  66
  67         struct bus_type_private *p;
  68 };
  69
  70 extern int __must_check bus_register(struct bus_type *bus);
  71 extern void bus_unregister(struct bus_type *bus);
  72
  73 extern int __must_check bus_rescan_devices(struct bus_type *bus);
  74
  75 /* iterator helpers for buses */
  76
  77 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
  78                      int (*fn)(struct device *dev, void *data));
  79 struct device *bus_find_device(struct bus_type *bus, struct device *start,
  80                                void *data,
  81                                int (*match)(struct device *dev, void *data));
  82 struct device *bus_find_device_by_name(struct bus_type *bus,
  83                                        struct device *start,
  84                                        const char *name);
  85
  86 int __must_check bus_for_each_drv(struct bus_type *bus,
  87                                   struct device_driver *start, void *data,
  88                                   int (*fn)(struct device_driver *, void *));
  89
  90 void bus_sort_breadthfirst(struct bus_type *bus,
  91                            int (*compare)(const struct device *a,
  92                                           const struct device *b));
  93 /*
  94  * Bus notifiers: Get notified of addition/removal of devices
  95  * and binding/unbinding of drivers to devices.
  96  * In the long run, it should be a replacement for the platform
  97  * notify hooks.
  98  */
  99 struct notifier_block;
 100
 101 extern int bus_register_notifier(struct bus_type *bus,
 102                                  struct notifier_block *nb);
 103 extern int bus_unregister_notifier(struct bus_type *bus,
 104                                    struct notifier_block *nb);
 105
 106 /* All 4 notifers below get called with the target struct device *
 107  * as an argument. Note that those functions are likely to be called
 108  * with the device lock held in the core, so be careful.
 109  */
 110 #define BUS_NOTIFY_ADD_DEVICE           0x00000001 /* device added */
 111 #define BUS_NOTIFY_DEL_DEVICE           0x00000002 /* device removed */
 112 #define BUS_NOTIFY_BOUND_DRIVER         0x00000003 /* driver bound to device */
 113 #define BUS_NOTIFY_UNBIND_DRIVER        0x00000004 /* driver about to be
 114                                                       unbound */
 115 #define BUS_NOTIFY_UNBOUND_DRIVER       0x00000005 /* driver is unbound
 116                                                       from the device */
 117
 118 extern struct kset *bus_get_kset(struct bus_type *bus);
 119 extern struct klist *bus_get_device_klist(struct bus_type *bus);
 120
 121 struct device_driver {
 122         const char              *name;
 123         struct bus_type         *bus;
 124
 125         struct module           *owner;
 126         const char              *mod_name;      /* used for built-in modules */
 127
 128         bool suppress_bind_attrs;       /* disables bind/unbind via sysfs */
 129
 130         int (*probe) (struct device *dev);
 131         int (*remove) (struct device *dev);
 132         void (*shutdown) (struct device *dev);
 133         int (*suspend) (struct device *dev, pm_message_t state);
 134         int (*resume) (struct device *dev);
 135         const struct attribute_group **groups;
 136
 137         const struct dev_pm_ops *pm;
 138
 139         struct driver_private *p;
 140 };
 141
 142
 143 extern int __must_check driver_register(struct device_driver *drv);
 144 extern void driver_unregister(struct device_driver *drv);
 145
 146 extern struct device_driver *get_driver(struct device_driver *drv);
 147 extern void put_driver(struct device_driver *drv);
 148 extern struct device_driver *driver_find(const char *name,
 149                                          struct bus_type *bus);
 150 extern int driver_probe_done(void);
 151 extern void wait_for_device_probe(void);
 152
 153
 154 /* sysfs interface for exporting driver attributes */
 155
 156 struct driver_attribute {
 157         struct attribute attr;
 158         ssize_t (*show)(struct device_driver *driver, char *buf);
 159         ssize_t (*store)(struct device_driver *driver, const char *buf,
 160                          size_t count);
 161 };
 162
 163 #define DRIVER_ATTR(_name, _mode, _show, _store)        \
 164 struct driver_attribute driver_attr_##_name =           \
 165         __ATTR(_name, _mode, _show, _store)
 166
 167 extern int __must_check driver_create_file(struct device_driver *driver,
 168                                         const struct driver_attribute *attr);
 169 extern void driver_remove_file(struct device_driver *driver,
 170                                const struct driver_attribute *attr);
 171
 172 extern int __must_check driver_add_kobj(struct device_driver *drv,
 173                                         struct kobject *kobj,
 174                                         const char *fmt, ...);
 175
 176 extern int __must_check driver_for_each_device(struct device_driver *drv,
 177                                                struct device *start,
 178                                                void *data,
 179                                                int (*fn)(struct device *dev,
 180                                                          void *));
 181 struct device *driver_find_device(struct device_driver *drv,
 182                                   struct device *start, void *data,
 183                                   int (*match)(struct device *dev, void *data));
 184
 185 /*
 186  * device classes
 187  */
 188 struct class {
 189         const char              *name;
 190         struct module           *owner;
 191
 192         struct class_attribute          *class_attrs;
 193         struct device_attribute         *dev_attrs;
 194         struct kobject                  *dev_kobj;
 195
 196         int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
 197         char *(*devnode)(struct device *dev, mode_t *mode);
 198
 199         void (*class_release)(struct class *class);
 200         void (*dev_release)(struct device *dev);
 201
 202         int (*suspend)(struct device *dev, pm_message_t state);
 203         int (*resume)(struct device *dev);
 204
 205         const struct dev_pm_ops *pm;
 206
 207         struct class_private *p;
 208 };
 209
 210 struct class_dev_iter {
 211         struct klist_iter               ki;
 212         const struct device_type        *type;
 213 };
 214
 215 extern struct kobject *sysfs_dev_block_kobj;
 216 extern struct kobject *sysfs_dev_char_kobj;
 217 extern int __must_check __class_register(struct class *class,
 218                                          struct lock_class_key *key);
 219 extern void class_unregister(struct class *class);
 220
 221 /* This is a #define to keep the compiler from merging different
 222  * instances of the __key variable */
 223 #define class_register(class)                   \
 224 ({                                              \
 225         static struct lock_class_key __key;     \
 226         __class_register(class, &__key);        \
 227 })
 228
 229 struct class_compat;
 230 struct class_compat *class_compat_register(const char *name);
 231 void class_compat_unregister(struct class_compat *cls);
 232 int class_compat_create_link(struct class_compat *cls, struct device *dev,
 233                              struct device *device_link);
 234 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
 235                               struct device *device_link);
 236
 237 extern void class_dev_iter_init(struct class_dev_iter *iter,
 238                                 struct class *class,
 239                                 struct device *start,
 240                                 const struct device_type *type);
 241 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
 242 extern void class_dev_iter_exit(struct class_dev_iter *iter);
 243
 244 extern int class_for_each_device(struct class *class, struct device *start,
 245                                  void *data,
 246                                  int (*fn)(struct device *dev, void *data));
 247 extern struct device *class_find_device(struct class *class,
 248                                         struct device *start, void *data,
 249                                         int (*match)(struct device *, void *));
 250
 251 struct class_attribute {
 252         struct attribute attr;
 253         ssize_t (*show)(struct class *class, struct class_attribute *attr,
 254                         char *buf);
 255         ssize_t (*store)(struct class *class, struct class_attribute *attr,
 256                         const char *buf, size_t count);
 257 };
 258
 259 #define CLASS_ATTR(_name, _mode, _show, _store)                 \
 260 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
 261
 262 extern int __must_check class_create_file(struct class *class,
 263                                           const struct class_attribute *attr);
 264 extern void class_remove_file(struct class *class,
 265                               const struct class_attribute *attr);
 266
 267 /* Simple class attribute that is just a static string */
 268
 269 struct class_attribute_string {
 270         struct class_attribute attr;
 271         char *str;
 272 };
 273
 274 /* Currently read-only only */
 275 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
 276         { __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
 277 #define CLASS_ATTR_STRING(_name, _mode, _str) \
 278         struct class_attribute_string class_attr_##_name = \
 279                 _CLASS_ATTR_STRING(_name, _mode, _str)
 280
 281 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
 282                         char *buf);
 283
 284 struct class_interface {
 285         struct list_head        node;
 286         struct class            *class;
 287
 288         int (*add_dev)          (struct device *, struct class_interface *);
 289         void (*remove_dev)      (struct device *, struct class_interface *);
 290 };
 291
 292 extern int __must_check class_interface_register(struct class_interface *);
 293 extern void class_interface_unregister(struct class_interface *);
 294
 295 extern struct class * __must_check __class_create(struct module *owner,
 296                                                   const char *name,
 297                                                   struct lock_class_key *key);
 298 extern void class_destroy(struct class *cls);
 299
 300 /* This is a #define to keep the compiler from merging different
 301  * instances of the __key variable */
 302 #define class_create(owner, name)               \
 303 ({                                              \
 304         static struct lock_class_key __key;     \
 305         __class_create(owner, name, &__key);    \
 306 })
 307
 308 /*
 309  * The type of device, "struct device" is embedded in. A class
 310  * or bus can contain devices of different types
 311  * like "partitions" and "disks", "mouse" and "event".
 312  * This identifies the device type and carries type-specific
 313  * information, equivalent to the kobj_type of a kobject.
 314  * If "name" is specified, the uevent will contain it in
 315  * the DEVTYPE variable.
 316  */
 317 struct device_type {
 318         const char *name;
 319         const struct attribute_group **groups;
 320         int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
 321         char *(*devnode)(struct device *dev, mode_t *mode);
 322         void (*release)(struct device *dev);
 323
 324         const struct dev_pm_ops *pm;
 325 };
 326
 327 /* interface for exporting device attributes */
 328 struct device_attribute {
 329         struct attribute        attr;
 330         ssize_t (*show)(struct device *dev, struct device_attribute *attr,
 331                         char *buf);
 332         ssize_t (*store)(struct device *dev, struct device_attribute *attr,
 333                          const char *buf, size_t count);
 334 };
 335
 336 #define DEVICE_ATTR(_name, _mode, _show, _store) \
 337 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
 338
 339 extern int __must_check device_create_file(struct device *device,
 340                                         const struct device_attribute *entry);
 341 extern void device_remove_file(struct device *dev,
 342                                const struct device_attribute *attr);
 343 extern int __must_check device_create_bin_file(struct device *dev,
 344                                         const struct bin_attribute *attr);
 345 extern void device_remove_bin_file(struct device *dev,
 346                                    const struct bin_attribute *attr);
 347 extern int device_schedule_callback_owner(struct device *dev,
 348                 void (*func)(struct device *dev), struct module *owner);
 349
 350 /* This is a macro to avoid include problems with THIS_MODULE */
 351 #define device_schedule_callback(dev, func)                     \
 352         device_schedule_callback_owner(dev, func, THIS_MODULE)
 353
 354 /* device resource management */
 355 typedef void (*dr_release_t)(struct device *dev, void *res);
 356 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
 357
 358 #ifdef CONFIG_DEBUG_DEVRES
 359 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
 360                              const char *name);
 361 #define devres_alloc(release, size, gfp) \
 362         __devres_alloc(release, size, gfp, #release)
 363 #else
 364 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
 365 #endif
 366 extern void devres_free(void *res);
 367 extern void devres_add(struct device *dev, void *res);
 368 extern void *devres_find(struct device *dev, dr_release_t release,
 369                          dr_match_t match, void *match_data);
 370 extern void *devres_get(struct device *dev, void *new_res,
 371                         dr_match_t match, void *match_data);
 372 extern void *devres_remove(struct device *dev, dr_release_t release,
 373                            dr_match_t match, void *match_data);
 374 extern int devres_destroy(struct device *dev, dr_release_t release,
 375                           dr_match_t match, void *match_data);
 376
 377 /* devres group */
 378 extern void * __must_check devres_open_group(struct device *dev, void *id,
 379                                              gfp_t gfp);
 380 extern void devres_close_group(struct device *dev, void *id);
 381 extern void devres_remove_group(struct device *dev, void *id);
 382 extern int devres_release_group(struct device *dev, void *id);
 383
 384 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
 385 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
 386 extern void devm_kfree(struct device *dev, void *p);
 387
 388 struct device_dma_parameters {
 389         /*
 390          * a low level driver may set these to teach IOMMU code about
 391          * sg limitations.
 392          */
 393         unsigned int max_segment_size;
 394         unsigned long segment_boundary_mask;
 395 };
 396
 397 struct device {
 398         struct device           *parent;
 399
 400         struct device_private   *p;
 401
 402         struct kobject kobj;
 403         const char              *init_name; /* initial name of the device */
 404         struct device_type      *type;
 405
 406         struct mutex            mutex;  /* mutex to synchronize calls to
 407                                          * its driver.
 408                                          */
 409
 410         struct bus_type *bus;           /* type of bus device is on */
 411         struct device_driver *driver;   /* which driver has allocated this
 412                                            device */
 413         void            *platform_data; /* Platform specific data, device
 414                                            core doesn't touch it */
 415         struct dev_pm_info      power;
 416
 417 #ifdef CONFIG_NUMA
 418         int             numa_node;      /* NUMA node this device is close to */
 419 #endif
 420         u64             *dma_mask;      /* dma mask (if dma'able device) */
 421         u64             coherent_dma_mask;/* Like dma_mask, but for
 422                                              alloc_coherent mappings as
 423                                              not all hardware supports
 424                                              64 bit addresses for consistent
 425                                              allocations such descriptors. */
 426
 427         struct device_dma_parameters *dma_parms;
 428
 429         struct list_head        dma_pools;      /* dma pools (if dma'ble) */
 430
 431         struct dma_coherent_mem *dma_mem; /* internal for coherent mem
 432                                              override */
 433         /* arch specific additions */
 434         struct dev_archdata     archdata;
 435
 436         dev_t                   devt;   /* dev_t, creates the sysfs "dev" */
 437
 438         spinlock_t              devres_lock;
 439         struct list_head        devres_head;
 440
 441         struct klist_node       knode_class;
 442         struct class            *class;
 443         const struct attribute_group **groups;  /* optional groups */
 444
 445         void    (*release)(struct device *dev);
 446 };
 447
 448 /* Get the wakeup routines, which depend on struct device */
 449 #include <linux/pm_wakeup.h>
 450
 451 static inline const char *dev_name(const struct device *dev)
 452 {
 453         /* Use the init name until the kobject becomes available */
 454         if (dev->init_name)
 455                 return dev->init_name;
 456
 457         return kobject_name(&dev->kobj);
 458 }
 459
 460 extern int dev_set_name(struct device *dev, const char *name, ...)
 461                         __attribute__((format(printf, 2, 3)));
 462
 463 #ifdef CONFIG_NUMA
 464 static inline int dev_to_node(struct device *dev)
 465 {
 466         return dev->numa_node;
 467 }
 468 static inline void set_dev_node(struct device *dev, int node)
 469 {
 470         dev->numa_node = node;
 471 }
 472 #else
 473 static inline int dev_to_node(struct device *dev)
 474 {
 475         return -1;
 476 }
 477 static inline void set_dev_node(struct device *dev, int node)
 478 {
 479 }
 480 #endif
 481
 482 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
 483 {
 484         return dev->kobj.uevent_suppress;
 485 }
 486
 487 static inline void dev_set_uevent_suppress(struct device *dev, int val)
 488 {
 489         dev->kobj.uevent_suppress = val;
 490 }
 491
 492 static inline int device_is_registered(struct device *dev)
 493 {
 494         return dev->kobj.state_in_sysfs;
 495 }
 496
 497 static inline void device_enable_async_suspend(struct device *dev)
 498 {
 499         if (dev->power.status == DPM_ON)
 500                 dev->power.async_suspend = true;
 501 }
 502
 503 static inline void device_disable_async_suspend(struct device *dev)
 504 {
 505         if (dev->power.status == DPM_ON)
 506                 dev->power.async_suspend = false;
 507 }
 508
 509 static inline bool device_async_suspend_enabled(struct device *dev)
 510 {
 511         return !!dev->power.async_suspend;
 512 }
 513
 514 static inline void device_lock(struct device *dev)
 515 {
 516         mutex_lock(&dev->mutex);
 517 }
 518
 519 static inline int device_trylock(struct device *dev)
 520 {
 521         return mutex_trylock(&dev->mutex);
 522 }
 523
 524 static inline void device_unlock(struct device *dev)
 525 {
 526         mutex_unlock(&dev->mutex);
 527 }
 528
 529 void driver_init(void);
 530
 531 /*
 532  * High level routines for use by the bus drivers
 533  */
 534 extern int __must_check device_register(struct device *dev);
 535 extern void device_unregister(struct device *dev);
 536 extern void device_initialize(struct device *dev);
 537 extern int __must_check device_add(struct device *dev);
 538 extern void device_del(struct device *dev);
 539 extern int device_for_each_child(struct device *dev, void *data,
 540                      int (*fn)(struct device *dev, void *data));
 541 extern struct device *device_find_child(struct device *dev, void *data,
 542                                 int (*match)(struct device *dev, void *data));
 543 extern int device_rename(struct device *dev, char *new_name);
 544 extern int device_move(struct device *dev, struct device *new_parent,
 545                        enum dpm_order dpm_order);
 546 extern const char *device_get_devnode(struct device *dev,
 547                                       mode_t *mode, const char **tmp);
 548 extern void *dev_get_drvdata(const struct device *dev);
 549 extern void dev_set_drvdata(struct device *dev, void *data);
 550
 551 /*
 552  * Root device objects for grouping under /sys/devices
 553  */
 554 extern struct device *__root_device_register(const char *name,
 555                                              struct module *owner);
 556 static inline struct device *root_device_register(const char *name)
 557 {
 558         return __root_device_register(name, THIS_MODULE);
 559 }
 560 extern void root_device_unregister(struct device *root);
 561
 562 static inline void *dev_get_platdata(const struct device *dev)
 563 {
 564         return dev->platform_data;
 565 }
 566
 567 /*
 568  * Manual binding of a device to driver. See drivers/base/bus.c
 569  * for information on use.
 570  */
 571 extern int __must_check device_bind_driver(struct device *dev);
 572 extern void device_release_driver(struct device *dev);
 573 extern int  __must_check device_attach(struct device *dev);
 574 extern int __must_check driver_attach(struct device_driver *drv);
 575 extern int __must_check device_reprobe(struct device *dev);
 576
 577 /*
 578  * Easy functions for dynamically creating devices on the fly
 579  */
 580 extern struct device *device_create_vargs(struct class *cls,
 581                                           struct device *parent,
 582                                           dev_t devt,
 583                                           void *drvdata,
 584                                           const char *fmt,
 585                                           va_list vargs);
 586 extern struct device *device_create(struct class *cls, struct device *parent,
 587                                     dev_t devt, void *drvdata,
 588                                     const char *fmt, ...)
 589                                     __attribute__((format(printf, 5, 6)));
 590 extern void device_destroy(struct class *cls, dev_t devt);
 591
 592 /*
 593  * Platform "fixup" functions - allow the platform to have their say
 594  * about devices and actions that the general device layer doesn't
 595  * know about.
 596  */
 597 /* Notify platform of device discovery */
 598 extern int (*platform_notify)(struct device *dev);
 599
 600 extern int (*platform_notify_remove)(struct device *dev);
 601
 602
 603 /**
 604  * get_device - atomically increment the reference count for the device.
 605  *
 606  */
 607 extern struct device *get_device(struct device *dev);
 608 extern void put_device(struct device *dev);
 609
 610 extern void wait_for_device_probe(void);
 611
 612 #ifdef CONFIG_DEVTMPFS
 613 extern int devtmpfs_create_node(struct device *dev);
 614 extern int devtmpfs_delete_node(struct device *dev);
 615 extern int devtmpfs_mount(const char *mntdir);
 616 #else
 617 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
 618 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
 619 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
 620 #endif
 621
 622 /* drivers/base/power/shutdown.c */
 623 extern void device_shutdown(void);
 624
 625 /* drivers/base/sys.c */
 626 extern void sysdev_shutdown(void);
 627
 628 /* debugging and troubleshooting/diagnostic helpers. */
 629 extern const char *dev_driver_string(const struct device *dev);
 630 #define dev_printk(level, dev, format, arg...)  \
 631         printk(level "%s %s: " format , dev_driver_string(dev) , \
 632                dev_name(dev) , ## arg)
 633
 634 #define dev_emerg(dev, format, arg...)          \
 635         dev_printk(KERN_EMERG , dev , format , ## arg)
 636 #define dev_alert(dev, format, arg...)          \
 637         dev_printk(KERN_ALERT , dev , format , ## arg)
 638 #define dev_crit(dev, format, arg...)           \
 639         dev_printk(KERN_CRIT , dev , format , ## arg)
 640 #define dev_err(dev, format, arg...)            \
 641         dev_printk(KERN_ERR , dev , format , ## arg)
 642 #define dev_warn(dev, format, arg...)           \
 643         dev_printk(KERN_WARNING , dev , format , ## arg)
 644 #define dev_notice(dev, format, arg...)         \
 645         dev_printk(KERN_NOTICE , dev , format , ## arg)
 646 #define dev_info(dev, format, arg...)           \
 647         dev_printk(KERN_INFO , dev , format , ## arg)
 648
 649 #if defined(DEBUG)
 650 #define dev_dbg(dev, format, arg...)            \
 651         dev_printk(KERN_DEBUG , dev , format , ## arg)
 652 #elif defined(CONFIG_DYNAMIC_DEBUG)
 653 #define dev_dbg(dev, format, ...) do { \
 654         dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
 655         } while (0)
 656 #else
 657 #define dev_dbg(dev, format, arg...)            \
 658         ({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
 659 #endif
 660
 661 #ifdef VERBOSE_DEBUG
 662 #define dev_vdbg        dev_dbg
 663 #else
 664
 665 #define dev_vdbg(dev, format, arg...)           \
 666         ({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
 667 #endif
 668
 669 /*
 670  * dev_WARN() acts like dev_printk(), but with the key difference
 671  * of using a WARN/WARN_ON to get the message out, including the
 672  * file/line information and a backtrace.
 673  */
 674 #define dev_WARN(dev, format, arg...) \
 675         WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
 676
 677 /* Create alias, so I can be autoloaded. */
 678 #define MODULE_ALIAS_CHARDEV(major,minor) \
 679         MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
 680 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
 681         MODULE_ALIAS("char-major-" __stringify(major) "-*")
 682 #endif /* _DEVICE_H_ */