Linux-2.6驱动程序分层分离概念

下面以一个按键的实验作为驱动分离时间简单学习：

 #include <linux/module.h>
 #include <linux/version.h>
 
 #include <linux/init.h>
 
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/interrupt.h>
 #include <linux/list.h>
 #include <linux/timer.h>
 #include <linux/init.h>
 #include <linux/serial_core.h>
 #include <linux/platform_device.h>
 
 /* 分配/设置/注册一个platform_device */
 
 static struct resource led_resource[] = {
     [] = {
         .start = 0x56000050,
         .end   = 0x56000050 +  - ,
         .flags = IORESOURCE_MEM,
     },
     [] = {
         .start = ,
         .end   = ,
         .flags = IORESOURCE_IRQ,
     }
 
 };
 
 static void led_release(struct device * dev)
 {
 }
 
 static struct platform_device led_dev = {
     .name         = "myled",
     .id       = -,
     .num_resources    = ARRAY_SIZE(led_resource),
     .resource     = led_resource,
     .dev = {
         .release = led_release,
     },
 };
 
 static int led_dev_init(void)
 {
     platform_device_register(&led_dev);
     return ;
 }
 
 static void led_dev_exit(void)
 {
     platform_device_unregister(&led_dev);
 }
 
 module_init(led_dev_init);
 module_exit(led_dev_exit);
 
 MODULE_LICENSE("GPL");

led_dev.c

 /* 分配/设置/注册一个platform_driver */
 
 #include <linux/module.h>
 #include <linux/version.h>
 
 #include <linux/init.h>
 #include <linux/fs.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/sched.h>
 #include <linux/pm.h>
 #include <linux/sysctl.h>
 #include <linux/proc_fs.h>
 #include <linux/delay.h>
 #include <linux/platform_device.h>
 #include <linux/input.h>
 #include <linux/irq.h>
 #include <asm/uaccess.h>
 #include <asm/io.h>
 
 static int major;
 
 static struct class *cls;
 static volatile unsigned long *gpio_con;
 static volatile unsigned long *gpio_dat;
 static int pin;
 
 static int led_open(struct inode *inode, struct file *file)
 {
     //printk("first_drv_open\n");
     /* 配置为输出 */
     *gpio_con &= ~(0x3<<(pin*));
     *gpio_con |= (0x1<<(pin*));
     return ;
 }
 
 static ssize_t led_write(struct file *file, const char __user *buf, size_t count, loff_t * ppos)
 {
     int val;
 
     //printk("first_drv_write\n");
 
     copy_from_user(&val, buf, count); //    copy_to_user();
 
     if (val == )
     {
         // 点灯
         *gpio_dat &= ~(<<pin);
     }
     else
     {
         // 灭灯
         *gpio_dat |= (<<pin);
     }
 
     return ;
 }
 
 static struct file_operations led_fops = {
     .owner  =   THIS_MODULE,    /* 这是一个宏，推向编译模块时自动创建的__this_module变量 */
     .open   =   led_open,
     .write    =    led_write,
 };
 
 static int led_probe(struct platform_device *pdev)
 {
     struct resource        *res;
 
     /* 根据platform_device的资源进行ioremap */
     res = platform_get_resource(pdev, IORESOURCE_MEM, );
     gpio_con = ioremap(res->start, res->end - res->start + );
     gpio_dat = gpio_con + ;
 
     res = platform_get_resource(pdev, IORESOURCE_IRQ, );
     pin = res->start;
 
     /* 注册字符设备驱动程序 */
 
     printk("led_probe, found led\n");
 
     major = register_chrdev(, "myled", &led_fops);
 
     cls = class_create(THIS_MODULE, "myled");
 
     class_device_create(cls, NULL, MKDEV(major, ), NULL, "led"); /* /dev/led */
 
     return ;
 }
 
 static int led_remove(struct platform_device *pdev)
 {
     /* 卸载字符设备驱动程序 */
     /* iounmap */
     printk("led_remove, remove led\n");
 
     class_device_destroy(cls, MKDEV(major, ));
     class_destroy(cls);
     unregister_chrdev(major, "myled");
     iounmap(gpio_con);
 
     return ;
 }
 
 struct platform_driver led_drv = {
     .probe        = led_probe,
     .remove        = led_remove,
     .driver        = {
         .name    = "myled",
     }
 };
 
 static int led_drv_init(void)
 {
     platform_driver_register(&led_drv);
     return ;
 }
 
 static void led_drv_exit(void)
 {
     platform_driver_unregister(&led_drv);
 }
 
 module_init(led_drv_init);
 module_exit(led_drv_exit);
 
 MODULE_LICENSE("GPL");

led_drv.c

 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <stdio.h>
 
 /* led_test on
  * led_test off
  */
 int main(int argc, char **argv)
 {
     int fd;
     int val = ;
     fd = open("/dev/led", O_RDWR);
     if (fd < )
     {
         printf("can't open!\n");
     }
     if (argc != )
     {
         printf("Usage :\n");
         printf("%s <on|off>\n", argv[]);
         return ;
     }
 
     if (strcmp(argv[], "on") == )
     {
         val  = ;
     }
     else
     {
         val = ;
     }
 
     write(fd, &val, );
     return ;
 }

led_test.c