+++ /dev/null
-/*
- * class_simple.c - a "simple" interface for classes for simple char devices.
- *
- * Copyright (c) 2003-2004 Greg Kroah-Hartman <greg@kroah.com>
- * Copyright (c) 2003-2004 IBM Corp.
- *
- * This file is released under the GPLv2
- *
- */
-
-#include <linux/config.h>
-#include <linux/device.h>
-#include <linux/err.h>
-
-struct class_simple {
- struct class class;
-};
-#define to_class_simple(d) container_of(d, struct class_simple, class)
-
-struct simple_dev {
- struct list_head node;
- struct class_device class_dev;
-};
-#define to_simple_dev(d) container_of(d, struct simple_dev, class_dev)
-
-static LIST_HEAD(simple_dev_list);
-static DEFINE_SPINLOCK(simple_dev_list_lock);
-
-static void release_simple_dev(struct class_device *class_dev)
-{
- struct simple_dev *s_dev = to_simple_dev(class_dev);
- kfree(s_dev);
-}
-
-static void class_simple_release(struct class *class)
-{
- struct class_simple *cs = to_class_simple(class);
- kfree(cs);
-}
-
-/**
- * class_simple_create - create a struct class_simple structure
- * @owner: pointer to the module that is to "own" this struct class_simple
- * @name: pointer to a string for the name of this class.
- *
- * This is used to create a struct class_simple pointer that can then be used
- * in calls to class_simple_device_add(). This is used when you do not wish to
- * create a full blown class support for a type of char devices.
- *
- * Note, the pointer created here is to be destroyed when finished by making a
- * call to class_simple_destroy().
- */
-struct class_simple *class_simple_create(struct module *owner, char *name)
-{
- struct class_simple *cs;
- int retval;
-
- cs = kmalloc(sizeof(*cs), GFP_KERNEL);
- if (!cs) {
- retval = -ENOMEM;
- goto error;
- }
- memset(cs, 0x00, sizeof(*cs));
-
- cs->class.name = name;
- cs->class.class_release = class_simple_release;
- cs->class.release = release_simple_dev;
-
- retval = class_register(&cs->class);
- if (retval)
- goto error;
-
- return cs;
-
-error:
- kfree(cs);
- return ERR_PTR(retval);
-}
-EXPORT_SYMBOL(class_simple_create);
-
-/**
- * class_simple_destroy - destroys a struct class_simple structure
- * @cs: pointer to the struct class_simple that is to be destroyed
- *
- * Note, the pointer to be destroyed must have been created with a call to
- * class_simple_create().
- */
-void class_simple_destroy(struct class_simple *cs)
-{
- if ((cs == NULL) || (IS_ERR(cs)))
- return;
-
- class_unregister(&cs->class);
-}
-EXPORT_SYMBOL(class_simple_destroy);
-
-/**
- * class_simple_device_add - adds a class device to sysfs for a character driver
- * @cs: pointer to the struct class_simple that this device should be registered to.
- * @dev: the dev_t for the device to be added.
- * @device: a pointer to a struct device that is assiociated with this class device.
- * @fmt: string for the class device's name
- *
- * This function can be used by simple char device classes that do not
- * implement their own class device registration. A struct class_device will
- * be created in sysfs, registered to the specified class. A "dev" file will
- * be created, showing the dev_t for the device. The pointer to the struct
- * class_device will be returned from the call. Any further sysfs files that
- * might be required can be created using this pointer.
- * Note: the struct class_simple passed to this function must have previously been
- * created with a call to class_simple_create().
- */
-struct class_device *class_simple_device_add(struct class_simple *cs, dev_t dev, struct device *device, const char *fmt, ...)
-{
- va_list args;
- struct simple_dev *s_dev = NULL;
- int retval;
-
- if ((cs == NULL) || (IS_ERR(cs))) {
- retval = -ENODEV;
- goto error;
- }
-
- s_dev = kmalloc(sizeof(*s_dev), GFP_KERNEL);
- if (!s_dev) {
- retval = -ENOMEM;
- goto error;
- }
- memset(s_dev, 0x00, sizeof(*s_dev));
-
- s_dev->class_dev.devt = dev;
- s_dev->class_dev.dev = device;
- s_dev->class_dev.class = &cs->class;
-
- va_start(args, fmt);
- vsnprintf(s_dev->class_dev.class_id, BUS_ID_SIZE, fmt, args);
- va_end(args);
- retval = class_device_register(&s_dev->class_dev);
- if (retval)
- goto error;
-
- spin_lock(&simple_dev_list_lock);
- list_add(&s_dev->node, &simple_dev_list);
- spin_unlock(&simple_dev_list_lock);
-
- return &s_dev->class_dev;
-
-error:
- kfree(s_dev);
- return ERR_PTR(retval);
-}
-EXPORT_SYMBOL(class_simple_device_add);
-
-/**
- * class_simple_set_hotplug - set the hotplug callback in the embedded struct class
- * @cs: pointer to the struct class_simple to hold the pointer
- * @hotplug: function pointer to the hotplug function
- *
- * Implement and set a hotplug function to add environment variables specific to this
- * class on the hotplug event.
- */
-int class_simple_set_hotplug(struct class_simple *cs,
- int (*hotplug)(struct class_device *dev, char **envp, int num_envp, char *buffer, int buffer_size))
-{
- if ((cs == NULL) || (IS_ERR(cs)))
- return -ENODEV;
- cs->class.hotplug = hotplug;
- return 0;
-}
-EXPORT_SYMBOL(class_simple_set_hotplug);
-
-/**
- * class_simple_device_remove - removes a class device that was created with class_simple_device_add()
- * @dev: the dev_t of the device that was previously registered.
- *
- * This call unregisters and cleans up a class device that was created with a
- * call to class_device_simple_add()
- */
-void class_simple_device_remove(dev_t dev)
-{
- struct simple_dev *s_dev = NULL;
- int found = 0;
-
- spin_lock(&simple_dev_list_lock);
- list_for_each_entry(s_dev, &simple_dev_list, node) {
- if (s_dev->class_dev.devt == dev) {
- found = 1;
- break;
- }
- }
- if (found) {
- list_del(&s_dev->node);
- spin_unlock(&simple_dev_list_lock);
- class_device_unregister(&s_dev->class_dev);
- } else {
- spin_unlock(&simple_dev_list_lock);
- }
-}
-EXPORT_SYMBOL(class_simple_device_remove);