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1、实验8-3驱动程序加载实验【实验目的】Ø掌握驱动程序加载方法。【实验步骤】第一步:利用vi编辑器,编写一个xsb_led.c驱动代码;1、增加驱动所需的头文件和变量#include#include#include#include#include#include#include#inc
2、lude#include#include#include#include#defineDEVICE_NAME"xsb_Led"#defineSEG_LED0x10500000#defineLed_MAJOR60staticcharLed_Buff=0x0;unsignedlong*Led_Address;staticstructclass_simple*l
3、ed_class;2、控制LED点亮函数staticvoidUpdateled(void){writew(Led_Buff,Led_Address);return;}3、实现LED驱动写操作函数staticssize_tLed_write(structfile*file,constchar*buffer,size_tcount,loff_t*ppos){if(count!=1){printk(KERN_EMERG"thecountofinputisnotone!!");return0;}copy
4、_from_user(&Led_Buff,buffer,1);Updateled();return1;}1、实现LED驱动的打开、释放函数以及文件操作结构体staticintLed_open(structinode*inode,structfile*filp){return0;}staticintLed_release(structinode*inode,structfile*filp){return0;}staticstructfile_operationsLed_fops={open:Led
5、_open,write:Led_write,release:Led_release,owner:THIS_MODULE,};2、实现LED驱动初始化函数staticint__initLed_init(void){intret;interr=0;Led_Address=ioremap(SEG_LED,4);ret=register_chrdev(Led_MAJOR,DEVICE_NAME,&Led_fops);if(ret<0){printk(DEVICE_NAME"can'tgetmajornu
6、mber");returnret;}led_class=class_simple_create(THIS_MODULE,DEVICE_NAME);if(IS_ERR(led_class)){err=PTR_ERR(led_class);gotoout_chrdev;}class_simple_device_add(led_class,MKDEV(Led_MAJOR,0),NULL,DEVICE_NAME);gotoOUT;out_chrdev:unregister_chrdev(Led_MA
7、JOR,DEVICE_NAME);OUT:returnerr;}1、实现七段数码管驱动模块退出函数与模块描述staticvoid__exitLed_exit(void){iounmap(Led_Address);class_simple_device_remove(MKDEV(Led_MAJOR,0));class_simple_destroy(led_class);unregister_chrdev(Led_MAJOR,DEVICE_NAME);}module_init(Led_init);m
8、odule_exit(Led_exit);MODULE_LICENSE("GPL");MODULE_AUTHOR("Dr.Ben.li");MODULE_DESCRIPTION("ThisisaLeddriverdemo");第一步:将xsb_led.c源码文件复制到目标平台linux内核的driver/char目录下;【图8-3-1】第二步:修改driver/char目录下的Makefile文件,增加如下项并保存:obj-$(CONFIG_XSB_LED)+=xsb_led.o【图8-3-2】