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 auxillary 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  * Auxillary 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
  37         /* Default operations for these types of devices */
  38         int     (*shutdown)(struct sys_device *);
  39         int     (*suspend)(struct sys_device *, pm_message_t state);
  40         int     (*resume)(struct sys_device *);
  41         struct kset             kset;
  42 };
  43
  44 struct sysdev_class_attribute {
  45         struct attribute attr;
  46         ssize_t (*show)(struct sysdev_class *, struct sysdev_class_attribute *,
  47                         char *);
  48         ssize_t (*store)(struct sysdev_class *, struct sysdev_class_attribute *,
  49                          const char *, size_t);
  50 };
  51
  52 #define _SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)            \
  53 {                                                               \
  54         .attr = {.name = __stringify(_name), .mode = _mode },   \
  55         .show   = _show,                                        \
  56         .store  = _store,                                       \
  57 }
  58
  59 #define SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)             \
  60         struct sysdev_class_attribute attr_##_name =            \
  61                 _SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)
  62
  63
  64 extern int sysdev_class_register(struct sysdev_class *);
  65 extern void sysdev_class_unregister(struct sysdev_class *);
  66
  67 extern int sysdev_class_create_file(struct sysdev_class *,
  68         struct sysdev_class_attribute *);
  69 extern void sysdev_class_remove_file(struct sysdev_class *,
  70         struct sysdev_class_attribute *);
  71 /**
  72  * Auxillary system device drivers.
  73  */
  74
  75 struct sysdev_driver {
  76         struct list_head        entry;
  77         int     (*add)(struct sys_device *);
  78         int     (*remove)(struct sys_device *);
  79         int     (*shutdown)(struct sys_device *);
  80         int     (*suspend)(struct sys_device *, pm_message_t state);
  81         int     (*resume)(struct sys_device *);
  82 };
  83
  84
  85 extern int sysdev_driver_register(struct sysdev_class *, struct sysdev_driver *);
  86 extern void sysdev_driver_unregister(struct sysdev_class *, struct sysdev_driver *);
  87
  88
  89 /**
  90  * sys_devices can be simplified a lot from regular devices, because they're
  91  * simply not as versatile.
  92  */
  93
  94 struct sys_device {
  95         u32             id;
  96         struct sysdev_class     * cls;
  97         struct kobject          kobj;
  98 };
  99
 100 extern int sysdev_register(struct sys_device *);
 101 extern void sysdev_unregister(struct sys_device *);
 102
 103
 104 struct sysdev_attribute {
 105         struct attribute        attr;
 106         ssize_t (*show)(struct sys_device *, struct sysdev_attribute *, char *);
 107         ssize_t (*store)(struct sys_device *, struct sysdev_attribute *,
 108                          const char *, size_t);
 109 };
 110
 111
 112 #define _SYSDEV_ATTR(_name, _mode, _show, _store)               \
 113 {                                                               \
 114         .attr = { .name = __stringify(_name), .mode = _mode },  \
 115         .show   = _show,                                        \
 116         .store  = _store,                                       \
 117 }
 118
 119 #define SYSDEV_ATTR(_name, _mode, _show, _store)                \
 120         struct sysdev_attribute attr_##_name =                  \
 121                 _SYSDEV_ATTR(_name, _mode, _show, _store);
 122
 123 extern int sysdev_create_file(struct sys_device *, struct sysdev_attribute *);
 124 extern void sysdev_remove_file(struct sys_device *, struct sysdev_attribute *);
 125
 126 /* Create/remove NULL terminated attribute list */
 127 static inline int
 128 sysdev_create_files(struct sys_device *d, struct sysdev_attribute **a)
 129 {
 130         return sysfs_create_files(&d->kobj, (const struct attribute **)a);
 131 }
 132
 133 static inline void
 134 sysdev_remove_files(struct sys_device *d, struct sysdev_attribute **a)
 135 {
 136         return sysfs_remove_files(&d->kobj, (const struct attribute **)a);
 137 }
 138
 139 struct sysdev_ext_attribute {
 140         struct sysdev_attribute attr;
 141         void *var;
 142 };
 143
 144 /*
 145  * Support for simple variable sysdev attributes.
 146  * The pointer to the variable is stored in a sysdev_ext_attribute
 147  */
 148
 149 /* Add more types as needed */
 150
 151 extern ssize_t sysdev_show_ulong(struct sys_device *, struct sysdev_attribute *,
 152                                 char *);
 153 extern ssize_t sysdev_store_ulong(struct sys_device *,
 154                         struct sysdev_attribute *, const char *, size_t);
 155 extern ssize_t sysdev_show_int(struct sys_device *, struct sysdev_attribute *,
 156                                 char *);
 157 extern ssize_t sysdev_store_int(struct sys_device *,
 158                         struct sysdev_attribute *, const char *, size_t);
 159
 160 #define _SYSDEV_ULONG_ATTR(_name, _mode, _var)                          \
 161         { _SYSDEV_ATTR(_name, _mode, sysdev_show_ulong, sysdev_store_ulong), \
 162           &(_var) }
 163 #define SYSDEV_ULONG_ATTR(_name, _mode, _var)                   \
 164         struct sysdev_ext_attribute attr_##_name =              \
 165                 _SYSDEV_ULONG_ATTR(_name, _mode, _var);
 166 #define _SYSDEV_INT_ATTR(_name, _mode, _var)                            \
 167         { _SYSDEV_ATTR(_name, _mode, sysdev_show_int, sysdev_store_int), \
 168           &(_var) }
 169 #define SYSDEV_INT_ATTR(_name, _mode, _var)                     \
 170         struct sysdev_ext_attribute attr_##_name =              \
 171                 _SYSDEV_INT_ATTR(_name, _mode, _var);
 172
 173 #endif /* _SYSDEV_H_ */