LDD3 example runs on arm11 based on linux-2.6.31 (1)

<!-- @page { margin: 0.79in } TD P { margin-bottom: 0in } P { margin-bottom: 0.08in } -->

LDD3 driver example run on ARM platform (1)

 

平台： i.mx31 3-stack (arm11)

内核版本 : Linux-2.6.31

 

代码：

 

Makefile:   ifeq ($(KERNELRELEASE),)       # Assume the source tree is where the running kernel was built   # You should set KERNELDIR in the environment if it's elsewhere   KERNELDIR ?= /home/mx31/codes/linux-2.6-imx/   # The current directory is passed to sub-makes as argument   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       .PHONY: modules modules_install clean       else   # called from kernel build system: just declare what our modules are   obj-m := hello.o hellop.o   endif

 

注： KERNELDIR指向你的平台所使用的内核树目录。

 

hello.c   /*   * $Id: hello.c,v 1.5 2004/10/26 03:32:21 corbet Exp $   */   #include <linux/init.h>   #include <linux/module.h>   MODULE_LICENSE("Dual BSD/GPL");       static int hello_init(void)   {   printk(KERN_ALERT "Hello, world/n");   return 0;   }       static void hello_exit(void)   {   printk(KERN_ALERT "Goodbye, cruel world/n");   }       module_init(hello_init);   module_exit(hello_exit);

 

hellop.c   /*   * $Id: hellop.c,v 1.4 2004/09/26 07:02:43 gregkh Exp $   */   #include <linux/init.h>   #include <linux/module.h>   #include <linux/moduleparam.h>       MODULE_LICENSE("Dual BSD/GPL");       /*   * These lines, although not shown in the book,   * are needed to make hello.c run properly even when   * your kernel has version support enabled   */           /*   * A couple of parameters that can be passed in: how many times we say   * hello, and to whom.   */     ///内核参数定义及声明 static char *whom = "world";   static int howmany = 1;   module_param(howmany, int, S_IRUGO); ///设置参数 howmany,使其可以通过命令行传递 module_param(whom, charp, S_IRUGO); ///S_IRUGO表示访问 sysfs中该模块参数的权限是只读     static int hello_init(void)   {   int i;   for (i = 0; i < howmany; i++)   printk(KERN_ALERT "(%d) Hello, %s/n", i, whom);   return 0;   }       static void hello_exit(void)   {   printk(KERN_ALERT "Goodbye, cruel world/n");   }       module_init(hello_init);   module_exit(hello_exit);

 

编译命令：

make ARCH=arm CROSS_COMPILE=/opt/freescale/usr/local/gcc-4.1.2-glibc-2.5-nptl-3/arm-none-linux-gnueabi/bin/arm-none-linux-gnueabi-

 

运行结果：

$ /home$ insmod hello.ko   Hello, world     $ /home$ insmod hellop.ko whom="Michael" howmany=3   (0) Hello, Michael   (1) Hello, Michael   (2) Hello, Michael   $ /home$ cat /sys/module/hellop/parameters/howmany   3   $ /home$ cat /sys/module/hellop/parameters/whom   Michael