讯为Exynos4412开发板例程及注释——LED

#include #include /*驱动注册的头文件，包含驱动的结构体和注册和卸载的函数*/#include /*注册杂项设备头文件*/#include /*注册设备节点的文件结构体*/#include /*Linux中申请GPIO的头文件*/#include /*三星平台的GPIO配置函数头文件*//*三星平台EXYNOS系列平台，GPIO配置参数宏定义头文件*/#include #include /*三星平台4412平台，GPIO宏定义头文件*/#include //vim arch/arm/mach-exynos/include/mach/gpio-exynos4.h#define DRIVER_NAME "hello_ctl"#define DEVICE_NAME "hello_ctl"MODULE_LICENSE("Dual BSD/GPL");MODULE_AUTHOR("TOPEET");/************************************************************************以下为设置设备节点*************************************************************************/static long hello_ioctl( struct file *files, unsigned int cmd, unsigned long arg){printk("cmd is %d,arg is %d\n",cmd,arg);if(cmd > 1){printk(KERN_EMERG "cmd is 0 or 1\n");}if(arg > 1){printk(KERN_EMERG "arg is only 1\n");}gpio_set_value(EXYNOS4_GPL2(0),cmd);return 0;}static int hello_release(struct inode *inode, struct file *file){printk(KERN_EMERG "hello release\n");return 0;}static int hello_open(struct inode *inode, struct file *file){printk(KERN_EMERG "hello open\n");return 0;}static struct file_operations hello_ops = {.owner = THIS_MODULE,.open = hello_open,.release = hello_release,.unlocked_ioctl = hello_ioctl,};static  struct miscdevice hello_dev = {.minor = MISC_DYNAMIC_MINOR,//自动分配.name = DEVICE_NAME,.fops = &hello_ops,};/*  misedevice 结构：struct miscdevice  {    int minor; //次设备号，若为 MISC_DYNAMIC_MINOR 自动分配    const char *name; //设备名    struct file_operations *fops; //设备操作    struct list_head list;    struct device *dev;    struct class_device *class;    char devfs_name[64];};*//************************************************************************以下为——驱动注册*************************************************************************///GPIO初始化在Probe中进行static int hello_probe(struct platform_device *pdv){int ret;printk(KERN_EMERG "\tinitialized\n");ret = gpio_request(EXYNOS4_GPL2(0),"LEDS");//其原型为 int gpio_request(unsigned gpio, const char *label) //先说说其参数，gpio则为你要申请的哪一个管脚，label则是为其取一个名字。if(ret < 0){printk(KERN_EMERG "gpio_request EXYNOS4_GPL2(0) failed!\n");return ret;}//extern int s3c_gpio_cfgpin(uint pin,uint to);//uint pin选择管脚，此处可以从exynos4412头文件得知，uint to为输入输出模式s3c_gpio_cfgpin(EXYNOS4_GPL2(0),S3C_GPIO_OUTPUT);//#define S3C_GPIO_OUTPUT (S3C_GPIO_SPECIAL(1))gpio_set_value(EXYNOS4_GPL2(0),0);misc_register(&hello_dev);return 0;}static int hello_remove(struct platform_device *pdv){printk(KERN_EMERG "\tremove\n");misc_deregister(&hello_dev);return 0;}static void hello_shutdown(struct platform_device *pdv){;}static int hello_suspend(struct platform_device *pdv,pm_message_t pmt){return 0;}static int hello_resume(struct platform_device *pdv){return 0;}struct platform_driver hello_driver = {.probe = hello_probe,.remove = hello_remove,.shutdown = hello_shutdown,.suspend = hello_suspend,.resume = hello_resume,.driver = {.name = DRIVER_NAME,.owner = THIS_MODULE,}};static int hello_init(void){int DriverState;printk(KERN_EMERG "HELLO WORLD enter!\n");DriverState = platform_driver_register(&hello_driver);printk(KERN_EMERG "\tDriverState is %d\n",DriverState);return 0;}static void hello_exit(void){printk(KERN_EMERG "HELLO WORLD exit!\n");platform_driver_unregister(&hello_driver);}module_init(hello_init);module_exit(hello_exit);#include #include #include #include #include #include main(){int fd;char *hello_node = "/dev/hello_ctl";/*O_RDWR只读打开,O_NDELAY非阻塞方式*/if((fd = open(hello_node,O_RDWR|O_NDELAY))<0){//返回值为-1则为错误printf("APP open %s failed",hello_node);}else{printf("APP open %s success",hello_node);ioctl(fd,1,1);sleep(3);ioctl(fd,0,1);sleep(3);ioctl(fd,1,1);}close(fd);}}