[linux驱动][linux驱动]设备驱动模型相关（一）——示例代码

1，以下为示例代码：

#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
MODULE_LICENSE("Dual BSD/GPL");
static char *Version = "2.0.1";
static int my_match(struct device *dev, struct device_driver *driver)
{
        return !strncmp(dev->kobj.name, driver->name, strlen(driver->name));
}

static void my_bus_release(struct device *dev)
{
        printk(KERN_DEBUG "my bus release
");
}
struct device my_bus = {
        .kobj.name   = "my_bus0",
        .release  = my_bus_release
};
struct bus_type my_bus_type = {
        .name = "my_bus",
        .match = my_match,
};
EXPORT_SYMBOL(my_bus);
EXPORT_SYMBOL(my_bus_type); 
static ssize_t show_bus_version(struct bus_type *bus, char *buf)
{
        return snprintf(buf, PAGE_SIZE, "%s
", Version);
}
static BUS_ATTR(version, S_IRUGO, show_bus_version, NULL);

static int __init my_bus_init(void)
{
        int ret;
        ret = bus_register(&my_bus_type);
        if (ret)
                return ret;
        if (bus_create_file(&my_bus_type, &bus_attr_version))
                printk(KERN_NOTICE "Fail to create version attribute!
");
        ret = device_register(&my_bus);
        if (ret)
                printk(KERN_NOTICE "Fail to register device:my_bus!
");

        return ret;
}
static void my_bus_exit(void)
{
        device_unregister(&my_bus);
        bus_unregister(&my_bus_type);
}

module_init(my_bus_init);
module_exit(my_bus_exit);

#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>

MODULE_LICENSE("Dual BSD/GPL");

extern struct device my_bus;
extern struct bus_type my_bus_type;
static void my_dev_release(struct device *dev)
{

}

struct device my_dev = {
        .init_name = "my_dev",
        .bus = &my_bus_type,
        .parent = &my_bus,     
        .release = my_dev_release,
};

static ssize_t mydev_show(struct device *dev,struct device_attribute *attr, char *buf)
{
        return sprintf(buf, "%s
", "This is my device!");
}

static DEVICE_ATTR(dev, S_IRUGO, mydev_show, NULL);

static int __init my_device_init(void)
{
        int ret = 0;
        ///strncpy(my_dev->kobj.name, "my_dev", strlen(my_dev->name));
        device_register(&my_dev);
        device_create_file(&my_dev, &dev_attr_dev);
        return ret;
}
static void my_device_exit(void)
{
        device_unregister(&my_dev);
}
module_init(my_device_init);
module_exit(my_device_exit);

#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>

MODULE_LICENSE("Dual BSD/GPL");
extern struct bus_type my_bus_type;
static int my_probe(struct device *dev)
{
    printk("Driver found device which my driver can handle!
");
    return 0;
}
static int my_remove(struct device *dev)
{
    printk("Driver found device unpluged!
");
    return 0;
}
struct device_driver my_driver = {
        .name = "my_dev",
        .bus = &my_bus_type,
        .probe = my_probe,
        .remove = my_remove,
};
static ssize_t mydriver_show(struct device_driver *driver, char *buf)
{
        return sprintf(buf, "%s
", "This is my driver!");
}
static DRIVER_ATTR(drv, S_IRUGO, mydriver_show, NULL);
static int __init my_driver_init(void)
{
        int ret = 0;
        driver_register(&my_driver);
        driver_create_file(&my_driver, &driver_attr_drv);
        return ret;
}
static void my_driver_exit(void)
{
        driver_unregister(&my_driver);
}
module_init(my_driver_init);
module_exit(my_driver_exit);