Both primary and secondary equipment numbers are 0

As the title

After loading the drive module , The primary device number and secondary device number of the printed character device are 0

reason

Code problem

Problem code

	st_ap3216cDev.dev_id = alloc_chrdev_region(&st_ap3216cDev.dev_id,0,1,NAME);
    st_ap3216cDev.major = MAJOR(st_ap3216cDev.dev_id);
    st_ap3216cDev.minor = MINOR(st_ap3216cDev.dev_id);
    printk("Major:%d minor:%d\n",st_ap3216cDev.major,st_ap3216cDev.minor);

It looks like there's nothing wrong
Actually, the code should be ：

	alloc_chrdev_region(&st_ap3216cDev.dev_id,0,1,NAME);
    st_ap3216cDev.major = MAJOR(st_ap3216cDev.dev_id);
    st_ap3216cDev.minor = MINOR(st_ap3216cDev.dev_id);
    printk("Major:%d minor:%d\n",st_ap3216cDev.major,st_ap3216cDev.minor);

• After successful application of equipment number , The return value is 0, Assign the return value to the device number variable , So the injection number and secondary equipment number printed are 0. Split ...