writing linux driver

1. Set up build environment

    >aptitude install build-essential

    >aptitude install linux-kernel-headers

 

2. Write sample code

#include <linux/init.h>#include <linux/module.h>#include <linux/kernel.h>int mydrv_init(void){ printk("Mydrv init ok!/n"); return 0;}void mydrv_exit(void){ printk("Mydrv exit ok!/n");}module_init(mydrv_init);module_exit(mydrv_exit);MODULE_LICENSE("Dual BSD/GPL"); 

 

3. Makefile

obj-m := mydrv.oKDIR := /lib/modules/$(shell uname -r)/buildPWD := $(shell pwd)default: $(MAKE) -C $(KDIR) SUBDIRS=$(PWD) modules 

 

4. After excute command make, the files will looks like this:

.├── Makefile├── modules.order├── Module.symvers├── mydrv.c├── mydrv.ko├── mydrv.mod.c├── mydrv.mod.o└── mydrv.o 

 

5. Then install/remove this module,you will look the message output by the driver.

 

    >insmod mydrv.ko

    >Mydrv init ok!

    >rmmod mydrv.ko

    >Mydrv exit ok!

 

    If you can not see it, please use this method:

    >dmesg | tail

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