【2017年整理】实现一个简单的linux字符设备驱动.docVIP

HYPERLINK /dreamer_shax/article/details/6580025 \o 实现一个简单的linux字符设备驱动 实现一个简单的linux字符设备驱动 步骤1：? 编写驱动程序 HYPERLINK /dreamer_shax/article/details/6580025 \o view plain view plain HYPERLINK /dreamer_shax/article/details/6580025 \o copy to clipboard copy to clipboard HYPERLINK /dreamer_shax/article/details/6580025 \o print print HYPERLINK /dreamer_shax/article/details/6580025 \o ? ?#include?linux/module.h ??#include?linux/init.h ??#include?linux/kernel.h ??#include?linux/cdev.h ??#include?linux/fs.h ??#include?linux/kdev_t.h ??#include?asm/uaccess.h ??#include?linux/device.h ??#define?DEVICE_NAME?cdev_zhangwei ??int?number_of_devices?=?1;????struct?cdev?mydev;??dev_t?dev?=?0;??char?data[128]?=?/0;?//?the?data?of?my?device ??struct?class?*myclass;??static?int?mydev_open(struct?inode?*inode,?struct?file?*file)??{??????pr_info(mydev?driver?open!/n);??????return?0;??}??static?int?mydev_release(struct?inode?*inode,?struct?file?*file)??{??????pr_info(mydev?driver?released!/n);??????return?0;??}??ssize_t?mydev_write(struct?file?*file,?const?char?__user?*buf,?size_t?count,?loff_t?*f_pos)??{??????ssize_t?ret?=?0;??????pr_info(mydev_write!/n);??????pr_info(writing?%d?bytes/n,?count);??????if?(count??127)???????????return?-ENOMEM;??????if?(count??0)???????????return?-EINVAL;??????if?(copy_from_user(data,?buf,?count))?{??????????ret?=?-EFAULT;??????}??????else?{??????????data[127]?=?/0;??????????pr_info(kernel?received:?%s/n,?data);??????????ret?=?count;??????}??????return?ret;??}??static?ssize_t?mydev_read(struct?file*?filp,?char*?buf,?size_t?len,loff_t*?off)??{??????if(?copy_to_user(buf,data,len)?)??????{??????????return?-EFAULT;??????}????????????return?len;??}??struct?file_operations?mydev_fops?=?{???????.owner?=?THIS_MODULE,??????.open?=?mydev_open,??????.read?=?mydev_read,??????.write?=?mydev_write,??????.release?=?mydev_release????????};??static?int?__init?mydev_init(void)??{??????int?result,?error;??????result?=?register_chrdev(0,?DEVICE_NAME,?mydev_fops);??????????pr_info(