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@@ -0,0 +1,329 @@
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+#include <linux/init.h>
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+#include <linux/module.h>
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+#include <linux/fs.h>
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+#include <linux/cdev.h>
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+#include <linux/slab.h>
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+#include <linux/uaccess.h>
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+#include <linux/device.h>
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+#include <linux/stat.h>
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+
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+#include <linux/sched.h>
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+#include <linux/timer.h>
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+#include <linux/workqueue.h>
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+
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+#include <linux/io.h>
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+#include "gpioregs.h"
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+
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+#define DEVICE_NAME "myname"
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+#define CLASS_NAME "myname_class"
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+#define BUFFER_SIZE 1024
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+
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+// 可以通过模块参数指定主设备号和次设备号
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+static int myname_major = 56; // 默认主设备号
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+static int myname_minor = 130; // 默认次设备号
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+module_param(myname_major, int, S_IRUGO);
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+module_param(myname_minor, int, S_IRUGO);
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+MODULE_PARM_DESC(myname_major, "Major device number");
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+MODULE_PARM_DESC(myname_minor, "Minor device number");
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+
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+static struct class *char_class = NULL;
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+static struct device *char_device = NULL;
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+static struct cdev my_cdev;
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+static dev_t dev_num;
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+
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+// 设备结构体
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+struct myname_dev
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+{
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+ char *buffer;
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+ size_t size;
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+ struct mutex lock;
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+ struct cdev cdev;
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+ struct delayed_work delay_work1;
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+ int board_id;
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+};
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+
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+static struct myname_dev *dev = NULL;
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+
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+static void delay_work_func(struct work_struct *work)
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+{
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+ printk(KERN_ERR "delay_work_func\n");
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+}
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+
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+// 文件打开操作
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+static int myname_open(struct inode *inode, struct file *filp)
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+{
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+ struct myname_dev *dev;
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+
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+ dev = container_of(inode->i_cdev, struct myname_dev, cdev);
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+ filp->private_data = dev;
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+
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+ printk(KERN_ERR "myname: Device opened (major=%d, minor=%d)\n",
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+ imajor(inode), iminor(inode));
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+ return 0;
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+}
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+
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+// 文件释放操作
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+static int myname_release(struct inode *inode, struct file *filp)
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+{
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+ // release_region(PORT_80, 1);
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+ printk(KERN_ERR "myname: Device closed\n");
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+ return 0;
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+}
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+
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+// 读操作 - 支持cat命令
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+static ssize_t myname_read(struct file *filp, char __user *buf,
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+ size_t count, loff_t *f_pos)
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+{
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+ struct myname_dev *dev = filp->private_data;
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+ ssize_t retval = 0;
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+ int ret = 0;
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+
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+ if (mutex_lock_interruptible(&dev->lock))
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+ return -ERESTARTSYS;
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+
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+ // 关键检查:是否已经读到文件末尾?
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+ if (*f_pos >= dev->size) {
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+ printk(KERN_DEBUG "myname: EOF reached (pos=%lld, size=%zu)\n",
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+ *f_pos, dev->size);
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+ mutex_unlock(&dev->lock);
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+ return 0; // 返回 0 告诉 cat 文件结束
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+ }
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+
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+ // 计算剩余可读字节数
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+ size_t available = dev->size - *f_pos;
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+
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+ // 确定本次读取的字节数
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+ if (count > available) {
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+ retval = available;
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+ } else {
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+ retval = count;
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+ }
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+
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+ printk(KERN_DEBUG "myname: Attempting to read %zu bytes from pos %lld\n",
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+ retval, *f_pos);
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+
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+ ret = copy_to_user(buf, dev->buffer + *f_pos, retval);
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+ if (ret != 0) {
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+ printk(KERN_ERR "myname: copy_to_user failed\n");
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+ mutex_unlock(&dev->lock);
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+ return -EFAULT;
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+ }
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+
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+ // 更新文件位置指针 - 这一步非常关键!
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+ *f_pos += retval;
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+
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+ printk(KERN_DEBUG "myname: Read %zu bytes, new pos=%lld\n", retval, *f_pos);
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+
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+ mutex_unlock(&dev->lock);
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+ return retval; // 返回实际读取的字节数
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+}
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+
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+// 写操作
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+static ssize_t myname_write(struct file *filp, const char __user *buf,
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+ size_t count, loff_t *f_pos)
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+{
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+ struct myname_dev *dev = filp->private_data;
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+ ssize_t retval = 0;
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+ size_t available;
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+ int ret = 0;
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+ return -1;
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+
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+ // 加锁
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+ if (mutex_lock_interruptible(&dev->lock))
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+ {
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+ return -ERESTARTSYS;
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+ }
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+
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+ // 计算可写数据量
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+ if (count > dev->size)
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+ {
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+ count = dev->size;
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+ }
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+
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+ // 拷贝数据
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+ ret = copy_from_user(dev->buffer, buf, count);
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+ if (ret != 0)
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+ {
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+ printk(KERN_ERR "myname: copy_from_user failed\n");
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+ goto out;
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+ }
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+
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+ dev->size = count;
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+
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+ printk(KERN_ERR "myname: Written %zu bytes\n", count);
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+
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+out:
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+ mutex_unlock(&dev->lock);
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+
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+ // 调度延迟工作
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+ if (ret == 0)
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+ {
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+ schedule_delayed_work(&dev->delay_work1, msecs_to_jiffies(10));
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+ }
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+ return count;
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+}
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+
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+// 文件操作结构体
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+static struct file_operations fops = {
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+ .owner = THIS_MODULE,
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+ .open = myname_open,
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+ .release = myname_release,
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+ .read = myname_read,
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+ .write = myname_write,
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+};
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+
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+// 获取board_id
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+int get_board_id(void)
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+{
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+ unsigned int board_id = 0;
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+
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+ if(board_id > 15)
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+ {
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+ printk(KERN_ERR "myname: Invalid board_id\n");
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+ return -EINVAL;
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+ }
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+ if(board_id == 0)
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+ {
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+ memcpy(dev->buffer, "ci (Ruby Ci)", strlen("ci (Ruby Ci)"));
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+ dev->size = strlen("ci (Ruby Ci)");
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+ }
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+ else if(board_id >= 1 && board_id <= 7)
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+ {
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+ memcpy(dev->buffer, "python (c18)", strlen("python (c18)"));
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+ dev->size = strlen("python (c18)");
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+ }
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+ else if(board_id >= 8 && board_id <= 11)
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+ {
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+ memcpy(dev->buffer, "selene", strlen("selene"));
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+ dev->size = strlen("selene");
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+ }
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+ else if(board_id >= 12 && board_id <= 15)
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+ {
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+ memcpy(dev->buffer, "cobra (Commander Ci)", strlen("cobra (Commander Ci)"));
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+ dev->size = strlen("cobra (Commander Ci)");
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+ }
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+ printk(KERN_ERR "myname: board_id = %d\n", board_id);
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+ return board_id;
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+}
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+
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+// 模块初始化
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+int myname_init(void)
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+{
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+ int result;
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+
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+ printk(KERN_ERR "myname: Initializing driver with major=%d, minor=%d\n",
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+ myname_major, myname_minor);
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+
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+ // 检查主设备号是否有效
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+ if (myname_major <= 0)
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+ {
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+ printk(KERN_ALERT "myname: Invalid major number %d\n", myname_major);
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+ return -EINVAL;
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+ }
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+
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+ // 构建设备号
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+ dev_num = MKDEV(myname_major, myname_minor);
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+
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+ // 注册设备号 - 使用指定的主设备号
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+ result = register_chrdev_region(dev_num, 1, DEVICE_NAME);
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+ if (result < 0)
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+ {
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+ printk(KERN_ALERT "myname: Failed to register major number %d\n", myname_major);
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+ printk(KERN_ALERT "myname: Try using a different major number\n");
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+ return result;
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+ }
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+
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+ printk(KERN_ERR "myname: Registered with major=%d, minor=%d\n",
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+ MAJOR(dev_num), MINOR(dev_num));
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+
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+ // 分配设备结构体
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+ dev = kmalloc(sizeof(struct myname_dev), GFP_KERNEL);
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+ if (!dev)
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+ {
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+ result = -ENOMEM;
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+ goto fail_malloc;
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+ }
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+ memset(dev, 0, sizeof(struct myname_dev));
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+
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+ // 分配缓冲区
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+ dev->buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL);
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+ if (!dev->buffer)
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+ {
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+ result = -ENOMEM;
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+ goto fail_buffer;
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+ }
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+ memset(dev->buffer, 0, BUFFER_SIZE);
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+ // 初始化互斥锁
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+ mutex_init(&dev->lock);
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+
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+ INIT_DELAYED_WORK(&dev->delay_work1, delay_work_func);
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+ dev->board_id = get_board_id();
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+ printk(KERN_ERR "myname: %s\n", dev->buffer);
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+
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+ // 初始化字符设备
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+ cdev_init(&dev->cdev, &fops);
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+ dev->cdev.owner = THIS_MODULE;
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+
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+ // 添加字符设备到系统
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+ result = cdev_add(&dev->cdev, dev_num, 1);
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+ if (result)
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+ {
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+ printk(KERN_ALERT "myname: Failed to add cdev\n");
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+ goto fail_cdev;
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+ }
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+
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+ // 创建设备类
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+ char_class = class_create(THIS_MODULE, CLASS_NAME);
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+ if (IS_ERR(char_class))
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+ {
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+ result = PTR_ERR(char_class);
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+ printk(KERN_ALERT "myname: Failed to create class\n");
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+ goto fail_class;
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+ }
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+
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+ // 创建设备
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+ char_device = device_create(char_class, NULL, dev_num, NULL, DEVICE_NAME);
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+ if (IS_ERR(char_device))
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+ {
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+ result = PTR_ERR(char_device);
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+ printk(KERN_ALERT "myname: Failed to create device\n");
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+ goto fail_device;
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+ }
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+
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+ printk(KERN_ERR "myname: Driver initialized successfully\n");
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+ printk(KERN_ERR "myname: Device node: /dev/%s (major=%d, minor=%d)\n",
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+ DEVICE_NAME, myname_major, myname_minor);
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+ return 0;
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+
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+fail_device:
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+ class_destroy(char_class);
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+fail_class:
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+ cdev_del(&dev->cdev);
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+fail_cdev:
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+ kfree(dev->buffer);
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+fail_buffer:
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+ kfree(dev);
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+fail_malloc:
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+ unregister_chrdev_region(dev_num, 1);
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+ return result;
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+}
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+
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+// 模块退出
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+void myname_exit(void)
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+{
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+ cancel_delayed_work_sync(&dev->delay_work1);
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+ device_destroy(char_class, dev_num);
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+ class_destroy(char_class);
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+
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+ if (dev)
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+ {
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+ cdev_del(&dev->cdev);
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+ if (dev->buffer)
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+ kfree(dev->buffer);
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+ kfree(dev);
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+ }
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+
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+ unregister_chrdev_region(dev_num, 1);
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+ printk(KERN_ERR "myname: Driver removed (major=%d, minor=%d)\n",
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+ myname_major, myname_minor);
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+}
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