国嵌内核驱动进阶班-7-1（Ioctl设备控制)--- 测试代码

 

 

驱动内容：

  1 #include <linux/module.h>
  2 #include <linux/types.h>
  3 #include <linux/fs.h>
  4 #include <linux/errno.h>
  5 #include <linux/mm.h>
  6 #include <linux/sched.h>
  7 #include <linux/init.h>
  8 #include <linux/cdev.h>
  9 #include <asm/io.h>
 10 #include <linux/slab.h>
 11 #include <asm/uaccess.h>
 12 
 13 #include "memdev.h"
 14 
 15 static int mem_major = MEMDEV_MAJOR;
 16 
 17 module_param(mem_major, int, S_IRUGO);
 18 
 19 struct mem_dev *mem_devp; /*设备结构体指针*/
 20 
 21 struct cdev cdev; 
 22 
 23 /*文件打开函数*/
 24 int mem_open(struct inode *inode, struct file *filp)
 25 {
 26     struct mem_dev *dev;
 27     
 28     /*获取次设备号*/
 29     int num = MINOR(inode->i_rdev);
 30 
 31     if (num >= MEMDEV_NR_DEVS) 
 32             return -ENODEV;
 33     dev = &mem_devp[num];
 34     
 35     /*将设备描述结构指针赋值给文件私有数据指针*/
 36     filp->private_data = dev;
 37     
 38     return 0; 
 39 }
 40 
 41 /*文件释放函数*/
 42 int mem_release(struct inode *inode, struct file *filp)
 43 {
 44   return 0;
 45 }
 46 
 47 /*IO操作*/
 48 long memdev_ioctl(struct file *filp,
 49                  unsigned int cmd, unsigned long arg)
 50  //long (*compat_ioctl) (struct file *filp, unsigned int cmd, 
 51  //                         unsigned long arg)
 52 {
 53     printk("<--- memdev_ioctl is call @@@ --->\n\n");
 54     
 55     int err = 0;
 56     int ret = 0;
 57     int ioarg = 0;
 58     
 59     /* 检测命令的有效性 */
 60     if (_IOC_TYPE(cmd) != MEMDEV_IOC_MAGIC) 
 61         return -EINVAL;
 62     if (_IOC_NR(cmd) > MEMDEV_IOC_MAXNR) 
 63         return -EINVAL;
 64 
 65     /* 根据命令类型，检测参数空间是否可以访问 */
 66     if (_IOC_DIR(cmd) & _IOC_READ)
 67         err = !access_ok(VERIFY_WRITE, (void *)arg, _IOC_SIZE(cmd));
 68     else if (_IOC_DIR(cmd) & _IOC_WRITE)
 69         err = !access_ok(VERIFY_READ, (void *)arg, _IOC_SIZE(cmd));
 70     if (err) 
 71         return -EFAULT;
 72 
 73     /* 根据命令，执行相应的操作 */
 74     switch(cmd) {
 75 
 76       /* 打印当前设备信息 */
 77       case MEMDEV_IOCPRINT:
 78           printk("<--- CMD MEMDEV_IOCPRINT Done--->\n\n");
 79         break;
 80       
 81       /* 获取参数 */
 82       case MEMDEV_IOCGETDATA: 
 83         ioarg = 1101;
 84         ret = __put_user(ioarg, (int *)arg);
 85         break;
 86       
 87       /* 设置参数 */
 88       case MEMDEV_IOCSETDATA: 
 89         ret = __get_user(ioarg, (int *)arg);
 90         printk("<--- In Kernel MEMDEV_IOCSETDATA ioarg = %d --->\n\n",ioarg);
 91         break;
 92 
 93       default:  
 94         return -EINVAL;
 95     }
 96     return ret;
 97 
 98 }
 99 
100 /*文件操作结构体*/
101 static const struct file_operations mem_fops =
102 {
103   .owner = THIS_MODULE,
104   .open = mem_open,
105   .release = mem_release,
106   .unlocked_ioctl = memdev_ioctl,
107 };
108 
109 /*设备驱动模块加载函数*/
110 static int memdev_init(void)
111 {
112   int result;
113   int i;
114 
115   dev_t devno = MKDEV(mem_major, 0);
116 
117   /* 静态申请设备号*/
118   if (mem_major)
119     result = register_chrdev_region(devno, 2, "memdev");
120   else  /* 动态分配设备号 */
121   {
122     result = alloc_chrdev_region(&devno, 0, 2, "memdev");
123     mem_major = MAJOR(devno);
124   }  
125   
126   if (result < 0)
127     return result;
128 
129   /*初始化cdev结构*/
130   cdev_init(&cdev, &mem_fops);
131   cdev.owner = THIS_MODULE;
132   cdev.ops = &mem_fops;
133   
134   /* 注册字符设备 */
135   cdev_add(&cdev, MKDEV(mem_major, 0), MEMDEV_NR_DEVS);
136    
137   /* 为设备描述结构分配内存*/
138   mem_devp = kmalloc(MEMDEV_NR_DEVS * sizeof(struct mem_dev), GFP_KERNEL);
139   if (!mem_devp)    /*申请失败*/
140   {
141     result =  - ENOMEM;
142     goto fail_malloc;
143   }
144   memset(mem_devp, 0, sizeof(struct mem_dev));
145   
146   /*为设备分配内存*/
147   for (i=0; i < MEMDEV_NR_DEVS; i++) 
148   {
149         mem_devp[i].size = MEMDEV_SIZE;
150         mem_devp[i].data = kmalloc(MEMDEV_SIZE, GFP_KERNEL);
151         memset(mem_devp[i].data, 0, MEMDEV_SIZE);
152   }
153     
154   return 0;
155 
156   fail_malloc: 
157   unregister_chrdev_region(devno, 1);
158   
159   return result;
160 }
161 
162 /*模块卸载函数*/
163 static void memdev_exit(void)
164 {
165   cdev_del(&cdev);   /*注销设备*/
166   kfree(mem_devp);     /*释放设备结构体内存*/
167   unregister_chrdev_region(MKDEV(mem_major, 0), 2); /*释放设备号*/
168 }
169 
170 MODULE_AUTHOR("David Xie");
171 MODULE_LICENSE("GPL");
172 
173 module_init(memdev_init);
174 module_exit(memdev_exit);
 1 #ifndef _MEMDEV_H_
 2 #define _MEMDEV_H_
 3 
 4 #include <linux/ioctl.h>
 5 
 6 #ifndef MEMDEV_MAJOR
 7 #define MEMDEV_MAJOR 0   /*预设的mem的主设备号*/
 8 #endif
 9 
10 #ifndef MEMDEV_NR_DEVS
11 #define MEMDEV_NR_DEVS 2    /*设备数*/
12 #endif
13 
14 #ifndef MEMDEV_SIZE
15 #define MEMDEV_SIZE 4096
16 #endif
17 
18 /*mem设备描述结构体*/
19 struct mem_dev                                     
20 {                                                        
21   char *data;                      
22   unsigned long size;       
23 };
24 
25 /* 定义幻数 */
26 #define MEMDEV_IOC_MAGIC  'k'
27 
28 /* 定义命令 */
29 #define MEMDEV_IOCPRINT   _IO(MEMDEV_IOC_MAGIC, 1)
30 #define MEMDEV_IOCGETDATA _IOR(MEMDEV_IOC_MAGIC, 2, int)
31 #define MEMDEV_IOCSETDATA _IOW(MEMDEV_IOC_MAGIC, 3, int)
32 
33 #define MEMDEV_IOC_MAXNR 3
34 
35 #endif /* _MEMDEV_H_ */

 

ifneq ($(KERNELRELEASE),)

obj-m := memdev.o

else
    
KDIR := /home/rpi/RpiLinux
all:
    make -C $(KDIR) M=$(PWD) modules ARCH=arm CROSS_COMPILE=/home/rpi/RpiTools/arm-bcm2708/arm-bcm2708hardfp-linux-gnueabi/bin/arm-bcm2708hardfp-linux-gnueabi-

clean:
    rm -f *.ko *.o *.mod.o *.mod.c *.symvers  modul*

endif

 

 

测试代码：

 1 #include <stdio.h>
 2 #include<sys/types.h>
 3 #include<sys/stat.h>
 4 #include<fcntl.h>
 5 
 6 #include "memdev.h"  /* 包含命令定义 */
 7 
 8 int main()
 9 {
10     int fd = 0;
11     int cmd;
12     int arg = 0;
13     char Buf[4096];
14     
15     
16     /*打开设备文件*/
17     fd = open("/dev/memdev0",O_RDWR);
18     if (fd < 0)
19     {
20         printf("Open Dev Mem0 Error!\n");
21         return -1;
22     }
23     
24     /* 调用命令MEMDEV_IOCPRINT */
25     printf("<--- Call MEMDEV_IOCPRINT --->\n");
26     cmd = MEMDEV_IOCPRINT;
27     if (ioctl(fd, cmd, &arg) < 0)
28         {
29             printf("Call cmd MEMDEV_IOCPRINT fail\n");
30             return -1;
31     }
32     
33     
34     /* 调用命令MEMDEV_IOCSETDATA */
35     printf("<--- Call MEMDEV_IOCSETDATA --->\n");
36     cmd = MEMDEV_IOCSETDATA;
37     arg = 2007;
38     if (ioctl(fd, cmd, &arg) < 0)
39         {
40             printf("Call cmd MEMDEV_IOCSETDATA fail\n");
41             return -1;
42     }
43 
44     
45     /* 调用命令MEMDEV_IOCGETDATA */
46     printf("<--- Call MEMDEV_IOCGETDATA --->\n");
47     cmd = MEMDEV_IOCGETDATA;
48     if (ioctl(fd, cmd, &arg) < 0)
49         {
50             printf("Call cmd MEMDEV_IOCGETDATA fail\n");
51             return -1;
52     }
53     printf("<--- In User Space MEMDEV_IOCGETDATA Get Data is %d --->\n\n",arg);    
54     
55     close(fd);
56     return 0;    
57 }

 

 

 

运行结果：

 1 pi@raspberrypi ~/test_driver $ sudo ./a.out 
 2 <--- Call MEMDEV_IOCPRINT --->
 3 <--- Call MEMDEV_IOCSETDATA --->
 4 <--- Call MEMDEV_IOCGETDATA --->
 5 <--- In User Space MEMDEV_IOCGETDATA Get Data is 1101 --->
 6 
 7 pi@raspberrypi ~/test_driver $ sudo dmesg
 8 [ 1382.384123] <--- memdev_ioctl is call @@@ --->
 9 [ 1382.384123] 
10 [ 1382.384158] <--- CMD MEMDEV_IOCPRINT Done--->
11 [ 1382.384158] 
12 [ 1382.384541] <--- memdev_ioctl is call @@@ --->
13 [ 1382.384541] 
14 [ 1382.384565] <--- In Kernel MEMDEV_IOCSETDATA ioarg = 2007 --->
15 [ 1382.384565] 
16 [ 1382.384816] <--- memdev_ioctl is call @@@ --->
17 [ 1382.384816]

 

posted @ 2015-06-03 00:36  renhl  阅读(264)  评论(0)  编辑  收藏  举报