• 设备驱动号 绑定文件描述符

    K1.c

    1. #include <linux/init.h>
    2. #include <linux/module.h>
    3. #include <linux/io.h>
    4. #include <linux/fs.h>
    5. #include <linux/types.h>
    6. #include <linux/gpio.h>
    7. #include <linux/cdev.h>
    8. #include <linux/device.h>
    9. #include "head.h"
    10.  
    11. char kbuf[128] = {};
    12. //定义三个指针指向映射后的虚拟内存
    13. unsigned int *vir_rcc;
    14. unsigned int *vir_moder_led1;
    15. unsigned int *vir_odr_led1;
    16. unsigned int *vir_moder_led2;
    17. unsigned int *vir_odr_led2;
    18. unsigned int *vir_moder_led3;
    19. unsigned int *vir_odr_led3;
    20.  
    21. struct cdev *cdev;
    22. unsigned int major=0;
    23. unsigned int minor=0;
    24. dev_t devno;
    25. struct class *cls;
    26. struct device *dev;
    27.  
    28. int mycdev_open(struct inode *inode, struct file *file)
    29. {
    30.     //获取打开的文件的次设备号
    31.     int min = MINOR(inode->i_rdev);
    32.     file->private_data = (void* )min;
    33.     printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    34.     return 0;
    35. }
    36. long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
    37. {
    38.     //获取打开文件的次设备号
    39.     int min = (int)file->private_data;
    40.     switch(min)
    41.     {
    42.         case 0:
    43.             switch(cmd)
    44.             {
    45.                 case LED_ON:
    46.                     (*vir_odr_led1) |= (0x1 << 10);
    47.                     break;
    48.                 case LED_OFF:
    49.                     (*vir_odr_led1) &= (~(0x1 << 10));
    50.                     break;
    51.             }
    52.             break;
    53.         case 1:
    54.              switch(cmd)
    55.             {
    56.                 case LED_ON:
    57.                     (*vir_odr_led2) |= (0x1 << 10);
    58.                     break;
    59.                 case LED_OFF:
    60.                     (*vir_odr_led2) &= (~(0x1 << 10));
    61.                     break;
    62.             }
    63.             break;
    64.         case 2:
    65.               switch(cmd)
    66.             {
    67.                 case LED_ON:
    68.                     (*vir_odr_led3) |= (0x1 << 10);
    69.                     break;
    70.                 case LED_OFF:
    71.                     (*vir_odr_led3) &= (~(0x1 << 10));
    72.                     break;
    73.             }
    74.             break;              
    75.     }
    76.     printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    77.     return 0;
    78. }
    79. int mycdev_close(struct inode *inode, struct file *file)
    80. {
    81.     printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    82.     return 0;
    83. }
    84. //定义操作方法结构体变量并赋值
    85. struct file_operations fops={
    86.     .open=mycdev_open,
    87.     .unlocked_ioctl=mycdev_ioctl,
    88.     .release=mycdev_close,
    89. };
    90. int all_led_init(void)
    91. {
    92.     //进行寄存器的地址映射
    93.     vir_rcc = ioremap(PHY_RCC,4);
    94.     if(vir_rcc == NULL)
    95.     {
    96.         printk("物理内存映射filed! %d\n",__LINE__);
    97.         return -EFAULT;
    98.     }
    99.  
    100.     vir_moder_led1 = ioremap(PHY_LED1_MODER,sizeof(gpio_t));
    101.     if(vir_moder_led1 == NULL)
    102.     {
    103.         printk("物理内存映射filed! %d\n",__LINE__);
    104.         return -EFAULT;
    105.     }
    106.     vir_odr_led1 = ioremap(PHY_LED1_ODR,sizeof(gpio_t));
    107.     if(vir_odr_led1 == NULL)
    108.     {
    109.         printk("物理内存映射filed! %d\n",__LINE__);
    110.         return -EFAULT;
    111.     }
    112.  
    113.     vir_moder_led2 = ioremap(PHY_LED2_MODER,sizeof(gpio_t));
    114.     if(vir_moder_led2 == NULL)
    115.     {
    116.         printk("物理内存映射filed! %d\n",__LINE__);
    117.         return -EFAULT;
    118.     }
    119.     vir_odr_led2 = ioremap(PHY_LED2_ODR,sizeof(gpio_t));
    120.     if(vir_odr_led2 == NULL)
    121.     {
    122.         printk("物理内存映射filed! %d\n",__LINE__);
    123.         return -EFAULT;
    124.     }
    125.  
    126.     vir_moder_led3 = vir_moder_led1;
    127.     if(vir_moder_led3 == NULL)
    128.     {
    129.         printk("物理内存映射filed! %d\n",__LINE__);
    130.         return -EFAULT;
    131.     }
    132.     vir_odr_led3 = vir_odr_led1;
    133.     if(vir_odr_led3 == NULL)
    134.     {
    135.         printk("物理内存映射filed! %d\n",__LINE__);
    136.         return -EFAULT;
    137.     }
    138.  
    139.     printk("物理内存映射成功!\n");
    140.  
    141.     //LED1寄存器初始化
    142.     (*vir_rcc) |= (0x3 << 4);         //GPIOE控制器时钟使能
    143.  
    144.     (*vir_moder_led1) &= (~(0x3 << 20));   //MODER[21:20] => 00
    145.     (*vir_moder_led1) |= (0x1 << 20);      //MODER[21:20] => 01
    146.     (*vir_odr_led1) &= (~(0x1 << 10));     //默认为关灯
    147.  
    148.     (*vir_moder_led2) &= (~(0x3 << 20));   //MODER[21:20] => 00
    149.     (*vir_moder_led2) |= (0x1 << 20);      //MODER[21:20] => 01
    150.     (*vir_odr_led2) &= (~(0x1 << 10));     //默认为关灯
    151.  
    152.     (*vir_moder_led3) &= (~(0x3 << 16));   //MODER[17:16] => 00
    153.     (*vir_moder_led3) |= (0x1 << 16);      //MODER[17:16] => 01
    154.     (*vir_odr_led3) &= (~(0x1 << 8));     //默认为关灯
    155.  
    156.     printk("寄存器初始化成功!\n");
    157.  
    158.     return 0;
    159. }
    160. static int __init mycdev_init(void)
    161. {
    162.     all_led_init();
    163.  
    164.     //1.申请一个驱动对象空间
    165.     int retu;
    166.     cdev=cdev_alloc();
    167.     if(cdev == NULL)
    168.     {
    169.         printk("申请驱动对象空间失败!\n");
    170.         retu = -EFAULT;
    171.         goto out1;
    172.     }
    173.     printk("申请驱动对象空间成功!\n");
    174.     //2.初始化设备对象
    175.     cdev_init(cdev,&fops);
    176.     //3.申请设备号
    177.     int ret=0;
    178.     if(major==0)
    179.     {
    180.         ret=alloc_chrdev_region(&devno,minor,3,"mycdev");
    181.         if(ret!=0)
    182.         {
    183.         printk("(动态)申请设备号失败，错误码 => %d \n",ret);
    184.         goto out2; 
    185.         }
    186.         major=MAJOR(devno);
    187.         minor=MINOR(devno);
    188.     }
    189.     else
    190.     {
    191.         ret=register_chrdev_region(MKDEV(major,minor),3,"mycdev");
    192.         if(ret!=0)
    193.         {
    194.         printk("(静态)申请设备号失败，错误码 => %d \n",ret);
    195.         goto out2; 
    196.         }
    197.     }
    198.  
    199.     printk("申请设备号成功!\n");
    200.     //4.注册设备驱动对象
    201.     int ret1;
    202.     ret1=cdev_add(cdev,MKDEV(major,minor),3);
    203.     if(ret1!=0)
    204.     {
    205.         printk("注册设备驱动对象失败，错误码 => %d \n",ret1);
    206.         goto out3;         
    207.     }
    208.     printk("注册设备驱动对象成功!\n");
    209.     //5.向上提交目录
    210.     cls=class_create(THIS_MODULE,"mycdev");
    211.     if(IS_ERR(cls))
    212.     {
    213.         printk("向上提交目录失败!\n");
    214.         goto out4;
    215.     }
    216.     printk("向上提交目录成功!\n");
    217.     //6.向上提交节点信息
    218.     int i;
    219.     for(i=0;i<3;i++)
    220.     {
    221.         dev=device_create(cls,NULL,MKDEV(major,i),NULL,"mycdev%d",i);
    222.         if(IS_ERR(dev))
    223.         {
    224.             printk("向上提交设备节点失败!\n");
    225.            goto out5;
    226.         }
    227.     }
    228.     printk("向上提交设备节点成功!\n");
    229.     return 0;
    230. out5:
    231.     for(--i;i>=0;i--)
    232.     {
    233.         device_destroy(cls,MKDEV(major,i));
    234.     }
    235.     class_destroy(cls);   
    236. out4:
    237.     cdev_del(cdev);
    238. out3:
    239.     unregister_chrdev_region(MKDEV(major,minor),3);
    240. out2:
    241.     kfree(cdev);
    242. out1:
    243.     return retu;
    244. }
    245. static void __exit mycdev_exit(void)
    246. {
    247.     //取消内存映射
    248.     iounmap(vir_rcc);
    249.  
    250.     iounmap(vir_moder_led1);
    251.     iounmap(vir_odr_led1);
    252.  
    253.     iounmap(vir_moder_led2);
    254.     iounmap(vir_odr_led2);
    255.  
    256.     iounmap(vir_moder_led3);
    257.     iounmap(vir_odr_led3);
    258.     //销毁设备节点信息
    259.     int i;
    260.     for(i=0;i>3;i++)
    261.     {
    262.         device_destroy(cls,MKDEV(major,i));
    263.     }
    264.     //销毁目录
    265.     class_destroy(cls);
    266.     //1.注销设备驱动
    267.     cdev_del(cdev);
    268.     //2.释放注册的设备号
    269.     unregister_chrdev_region(MKDEV(major,minor),3);
    270.     //释放对象空间
    271.     kfree(cdev);
    272.  
    273. }
    274. module_init(mycdev_init);
    275. module_exit(mycdev_exit);
    276. MODULE_LICENSE("GPL");

    test.c

    1. #include <stdio.h>
    2. #include <sys/types.h>
    3. #include <sys/stat.h>
    4. #include <sys/ioctl.h>
    5. #include <fcntl.h>
    6. #include <unistd.h>
    7. #include <string.h>
    8. #include "head.h"
    9. int main(int argc,const char * argv[])
    10. {
    11.     char buf[128] = {0};
    12.     int fd0 = open("/dev/mycdev0",O_RDWR);
    13.     if(fd0 < 0)
    14.     {
    15.         printf("文件/dev/mycdev0打开失败\n");
    16.         return -1;
    17.     }
    18.     printf("文件/dev/mycdev0打开成功\n");
    19.     int fd1 = open("/dev/mycdev1",O_RDWR);
    20.     if(fd1 < 0)
    21.     {
    22.         printf("文件/dev/mycdev1打开失败\n");
    23.         return -1;
    24.     }
    25.     printf("文件/dev/mycdev1打开成功\n");
    26.     int fd2 = open("/dev/mycdev2",O_RDWR);
    27.     if(fd2 < 0)
    28.     {
    29.         printf("文件/dev/mycdev2打开失败\n");
    30.         return -1;
    31.     }
    32.     printf("文件/dev/mycdev2打开成功\n");
    33.     int a=0;
    34.     int b=0;
    35.     while(1)
    36.     {
    37.         printf("输入要进行的操作：");
    38.         printf("0(关灯)1(开灯) >>  ");
    39.         scanf("%d",&a);
    40.         printf("请选择要控制的灯：1（LED1）2(LED2) 3(LED3) >> ");
    41.         scanf("%d",&b);
    42.         switch(a)
    43.         {
    44.             case 0://关灯
    45.                 switch(b)//哪个灯
    46.                 {
    47.                     case 0:
    48.                         ioctl(fd0,LED_OFF);
    49.                         break;
    50.                     case 1:
    51.                         ioctl(fd1,LED_OFF);
    52.                         break;
    53.                     case 2:
    54.                         ioctl(fd2,LED_OFF);
    55.                         break;                   
    56.                 }
    57.             break;
    58.             case 1://开灯
    59.                 switch(b)//哪个灯
    60.                 {
    61.                     case 0:
    62.                         ioctl(fd0,LED_ON);
    63.                         break;
    64.                     case 1:
    65.                         ioctl(fd1,LED_ON);
    66.                         break;
    67.                     case 2:
    68.                         ioctl(fd2,LED_ON);
    69.                         break;                   
    70.                 }
    71.             break;             
    72.         }
    73.  
    74.     }
    75.  
    76.  
    77.     close(fd0);
    78.     close(fd1);
    79.     close(fd2);
    80.     return 0;
    81. }

    head.h

    1. #ifndef __HEAD_H__
    2. #define __HEAD_H__
    3. typedef struct{
    4.     unsigned int MODER;
    5.     unsigned int OTYPER;
    6.     unsigned int OSPEEDR;
    7.     unsigned int PUPDR;
    8.     unsigned int IDR;
    9.     unsigned int ODR;
    10. }gpio_t;
    11. #define PHY_RCC        0x50000A28
    12.  
    13. #define PHY_LED1_MODER 0x50006000
    14. #define PHY_LED1_ODR   0x50006014
    15.  
    16. #define PHY_LED2_MODER 0x50007000
    17. #define PHY_LED2_ODR   0x50007014
    18. //构建功能码
    19. #define LED_ON _IO('l', 1)  //开灯
    20. #define LED_OFF _IO('l', 0)  //关灯
    21.  
    22. #endif

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  • 原文地址：https://blog.csdn.net/ainitjq1314/article/details/133999011