ARM-第七次

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4.修改Makefile文件,复制mini2440_hello_module那一行之后,进行修改

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5.然后保存退出
6.编译:make zImage
7.进入config界面:make menuconfig

• 选择Device Drivers --->

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• 选择Character devices

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• 选择My module sample,按空格键将M改为*号

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内核设备的编写

1.在用户自己创建的目录下:创建一个hello.c与Makefile的文件
2.在hello.c中

#include <linux/kernel.h>
#include <linux/module.h>

static int __init mini2440_hello_module_init(void)
{
    printk("Hello,Min2440 module is installed !\n");
    return 0;
}
static void __exit mini2440_hello_module_cleanup(void)
{
    printk("Good_bye,mini2440 module was removed!\n");
}
module_init(mini2440_hello_module_init);
module_exit(mini2440_hello_module_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jiang xiu bi");
MODULE_DESCRIPTION("This is example module!!");
MODULE_VERSION("V1.0.0");

• 在Makefile中

ifeq ($(KERNELRELEASE),)
KERNELDIR ?= /home/jxb/1612/1/sq1612/linux-2.6.32.2
PWD :=$(shell pwd)
modules:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules
modules_install:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install
clean:
    rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c .tmp_versions *.symvers *.order
.PHONLY:modules modules_install clean
else
obj-m :=hello.o
#obj-m :=hello2.o
endif

• 运行结果

3.代码升级,在hello.c中

#include <linux/kernel.h>
#include <linux/module.h>

//#define __init
//#define __exit
static int howmany=1;
static char * name="Jiang xiu bi";

static int __init mini2440_hello_module_init(void)
{
    printk("Hello,Min2440 module is installed !\n");
    printk("I am %s!\n",name);
    printk("I have %d mini2440 board!\n",howmany);
    return 0;
}
static void __exit mini2440_hello_module_cleanup(void)
{
    printk("Good_bye,mini2440 module was removed!\n");
}
module_init(mini2440_hello_module_init);
module_exit(mini2440_hello_module_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jiang xiu bi");
MODULE_DESCRIPTION("This is example module!!");
MODULE_VERSION("V1.0.0");

module_param(howmany,int,S_IRUGO);
module_param(name,charp,S_IRUGO);
EXPORT_SYMBOL(howmany);
EXPORT_SYMBOL(name);

• 在Makefile中

ifeq ($(KERNELRELEASE),)
KERNELDIR ?= /home/jxb/1612/1/sq1612/linux-2.6.32.2
PWD :=$(shell pwd)
modules:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules
modules_install:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install
clean:
    rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c .tmp_versions *.symvers *.order
.PHONLY:modules modules_install clean
else
obj-m :=hello.o
#obj-m :=hello2.o
endif

• 运行结果

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4. 再升级版,两个模块的,在hello.c中

#include <linux/kernel.h>
#include <linux/module.h>

//#define __init
//#define __exit
static int howmany=1;
static char * name="Jiang xiu bi";

static int __init mini2440_hello_module_init(void)
{
    printk("Hello,Min2440 module is installed !\n");
    printk("I am %s!\n",name);
    printk("I have %d mini2440 board!\n",howmany);
    return 0;
}
static void __exit mini2440_hello_module_cleanup(void)
{
    printk("Good_bye,mini2440 module was removed!\n");
}
module_init(mini2440_hello_module_init);
module_exit(mini2440_hello_module_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jiang xiu bi");
MODULE_DESCRIPTION("This is example module!!");
MODULE_VERSION("V1.0.0");

module_param(howmany,int,S_IRUGO);
module_param(name,charp,S_IRUGO);
EXPORT_SYMBOL(howmany);
EXPORT_SYMBOL(name);

• 在hello2.c中

#include <linux/kernel.h>
#include <linux/module.h>

//#define __init
//#define __
extern int howmany;
extern char * name;

static int __init mini2440_hello_module_init(void)
{
    printk("Hello,Min2440 module is installed !\n");
    printk("I am %s!\n",name);
    printk("I have %d mini2440 board!\n",howmany);
    return 0;
}
static void __exit mini2440_hello_module_cleanup(void)
{
    printk("Good_bye,mini2440 module was removed!\n");
}
module_init(mini2440_hello_module_init);
module_exit(mini2440_hello_module_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jiang xiu bi");
MODULE_DESCRIPTION("This is example module!!");
MODULE_VERSION("V1.0.0");

• 在Makefile中

ifeq ($(KERNELRELEASE),)
KERNELDIR ?= /home/jxb/1612/1/sq1612/linux-2.6.32.2
PWD :=$(shell pwd)
modules:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules
modules_install:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install
clean:
    rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c .tmp_versions *.symvers *.order
.PHONLY:modules modules_install clean
else
obj-m :=hello.o
obj-m :=hello2.o
endif

• 运行结果
  1.先运行模块1

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2.再运行模块2

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