include/linux/sysdev.h

   1 /**
   2  * System devices follow a slightly different driver model.
   3  * They don't need to do dynammic driver binding, can't be probed,
   4  * and don't reside on any type of peripheral bus.
   5  * So, we represent and treat them a little differently.
   6  *
   7  * We still have a notion of a driver for a system device, because we still
   8  * want to perform basic operations on these devices.
   9  *
  10  * We also support auxiliary drivers binding to devices of a certain class.
  11  *
  12  * This allows configurable drivers to register themselves for devices of
  13  * a certain type. And, it allows class definitions to reside in generic
  14  * code while arch-specific code can register specific drivers.
  15  *
  16  * Auxiliary drivers registered with a NULL cls are registered as drivers
  17  * for all system devices, and get notification calls for each device.
  18  */
  19
  20
  21 #ifndef _SYSDEV_H_
  22 #define _SYSDEV_H_
  23
  24 #include <linux/kobject.h>
  25 #include <linux/module.h>
  26 #include <linux/pm.h>
  27
  28
  29 struct sys_device;
  30 struct sysdev_class_attribute;
  31
  32 struct sysdev_class {
  33         const char *name;
  34         struct list_head        drivers;
  35         struct sysdev_class_attribute **attrs;
  36         struct kset             kset;
  37 #ifndef CONFIG_ARCH_NO_SYSDEV_OPS
  38         /* Default operations for these types of devices */
  39         int     (*shutdown)(struct sys_device *);
  40         int     (*suspend)(struct sys_device *, pm_message_t state);
  41         int     (*resume)(struct sys_device *);
  42 #endif
  43 };
  44
  45 struct sysdev_class_attribute {
  46         struct attribute attr;
  47         ssize_t (*show)(struct sysdev_class *, struct sysdev_class_attribute *,
  48                         char *);
  49         ssize_t (*store)(struct sysdev_class *, struct sysdev_class_attribute *,
  50                          const char *, size_t);
  51 };
  52
  53 #define _SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)            \
  54 {                                                               \
  55         .attr = {.name = __stringify(_name), .mode = _mode },   \
  56         .show   = _show,                                        \
  57         .store  = _store,                                       \
  58 }
  59
  60 #define SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)             \
  61         struct sysdev_class_attribute attr_##_name =            \
  62                 _SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)
  63
  64
  65 extern int sysdev_class_register(struct sysdev_class *);
  66 extern void sysdev_class_unregister(struct sysdev_class *);
  67
  68 extern int sysdev_class_create_file(struct sysdev_class *,
  69         struct sysdev_class_attribute *);
  70 extern void sysdev_class_remove_file(struct sysdev_class *,
  71         struct sysdev_class_attribute *);
  72 /**
  73  * Auxiliary system device drivers.
  74  */
  75
  76 struct sysdev_driver {
  77         struct list_head        entry;
  78         int     (*add)(struct sys_device *);
  79         int     (*remove)(struct sys_device *);
  80 #ifndef CONFIG_ARCH_NO_SYSDEV_OPS
  81         int     (*shutdown)(struct sys_device *);
  82         int     (*suspend)(struct sys_device *, pm_message_t state);
  83         int     (*resume)(struct sys_device *);
  84 #endif
  85 };
  86
  87
  88 extern int sysdev_driver_register(struct sysdev_class *, struct sysdev_driver *);
  89 extern void sysdev_driver_unregister(struct sysdev_class *, struct sysdev_driver *);
  90
  91
  92 /**
  93  * sys_devices can be simplified a lot from regular devices, because they're
  94  * simply not as versatile.
  95  */
  96
  97 struct sys_device {
  98         u32             id;
  99         struct sysdev_class     * cls;
 100         struct kobject          kobj;
 101 };
 102
 103 extern int sysdev_register(struct sys_device *);
 104 extern void sysdev_unregister(struct sys_device *);
 105
 106
 107 struct sysdev_attribute {
 108         struct attribute        attr;
 109         ssize_t (*show)(struct sys_device *, struct sysdev_attribute *, char *);
 110         ssize_t (*store)(struct sys_device *, struct sysdev_attribute *,
 111                          const char *, size_t);
 112 };
 113
 114
 115 #define _SYSDEV_ATTR(_name, _mode, _show, _store)               \
 116 {                                                               \
 117         .attr = { .name = __stringify(_name), .mode = _mode },  \
 118         .show   = _show,                                        \
 119         .store  = _store,                                       \
 120 }
 121
 122 #define SYSDEV_ATTR(_name, _mode, _show, _store)                \
 123         struct sysdev_attribute attr_##_name =                  \
 124                 _SYSDEV_ATTR(_name, _mode, _show, _store);
 125
 126 extern int sysdev_create_file(struct sys_device *, struct sysdev_attribute *);
 127 extern void sysdev_remove_file(struct sys_device *, struct sysdev_attribute *);
 128
 129 /* Create/remove NULL terminated attribute list */
 130 static inline int
 131 sysdev_create_files(struct sys_device *d, struct sysdev_attribute **a)
 132 {
 133         return sysfs_create_files(&d->kobj, (const struct attribute **)a);
 134 }
 135
 136 static inline void
 137 sysdev_remove_files(struct sys_device *d, struct sysdev_attribute **a)
 138 {
 139         return sysfs_remove_files(&d->kobj, (const struct attribute **)a);
 140 }
 141
 142 struct sysdev_ext_attribute {
 143         struct sysdev_attribute attr;
 144         void *var;
 145 };
 146
 147 /*
 148  * Support for simple variable sysdev attributes.
 149  * The pointer to the variable is stored in a sysdev_ext_attribute
 150  */
 151
 152 /* Add more types as needed */
 153
 154 extern ssize_t sysdev_show_ulong(struct sys_device *, struct sysdev_attribute *,
 155                                 char *);
 156 extern ssize_t sysdev_store_ulong(struct sys_device *,
 157                         struct sysdev_attribute *, const char *, size_t);
 158 extern ssize_t sysdev_show_int(struct sys_device *, struct sysdev_attribute *,
 159                                 char *);
 160 extern ssize_t sysdev_store_int(struct sys_device *,
 161                         struct sysdev_attribute *, const char *, size_t);
 162
 163 #define _SYSDEV_ULONG_ATTR(_name, _mode, _var)                          \
 164         { _SYSDEV_ATTR(_name, _mode, sysdev_show_ulong, sysdev_store_ulong), \
 165           &(_var) }
 166 #define SYSDEV_ULONG_ATTR(_name, _mode, _var)                   \
 167         struct sysdev_ext_attribute attr_##_name =              \
 168                 _SYSDEV_ULONG_ATTR(_name, _mode, _var);
 169 #define _SYSDEV_INT_ATTR(_name, _mode, _var)                            \
 170         { _SYSDEV_ATTR(_name, _mode, sysdev_show_int, sysdev_store_int), \
 171           &(_var) }
 172 #define SYSDEV_INT_ATTR(_name, _mode, _var)                     \
 173         struct sysdev_ext_attribute attr_##_name =              \
 174                 _SYSDEV_INT_ATTR(_name, _mode, _var);
 175
 176 #endif /* _SYSDEV_H_ */