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