platform 无非就是内核中有一条总线而已,方便移植!个人感觉没有跟自己创建总线是木有区别的!当然相关的函数内核就自己处理了,省事,呵呵!
1、内核代码
①、device.c
#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/platform_device.h>
MODULE_AUTHOR("_Justin");
MODULE_LICENSE("GPL");
static struct platform_device *my_device;
static int __init my_device_init(void)
{
int ret = 0;
printk("[Call my_device_init!]\n");
/* 分配结构 */
my_device = platform_device_alloc("my_dev",-1);
/* 注册设备 */
ret = platform_device_add(my_device);
/* 注册失败,释放相关内存 */
if(ret)
platform_device_put(my_device);
return ret;
}
static void __exit my_device_exit(void)
{
printk("[Call my_device_exit!]\n");
platform_device_unregister(my_device);
}
module_init(my_device_init);
module_exit(my_device_exit);
②、driver.c
#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/platform_device.h>
MODULE_AUTHOR("_Justin");
MODULE_LICENSE("GPL");
static int my_probe(struct device *dev)
{
printk("[Driver found device which my driver can handle!]\n");
return 0;
}
static int my_remove(struct device *dev)
{
printk("[Driver found device unpluged!]\n");
return 0;
}
static struct platform_driver my_driver =
{
.probe = my_probe,
.remove = my_remove,
.driver =
{
.owner = THIS_MODULE,
.name = "my_dev",
},
};
static int __init my_driver_init(void)
{
printk("[Call my_driver_init!]\n");
/* 注册平台驱动 */
return platform_driver_register(&my_driver);
}
static void __exit my_driver_exit(void)
{
printk("[Call my_driver_exit!]\n");
platform_driver_unregister(&my_driver);
}
module_init(my_driver_init);
module_exit(my_driver_exit);
③、Makefile
本来每个文件都对应一个 Makefile,为了省事,只贴一个!
ifneq ($(KERNELRELEASE),)
obj-m := driver.o
else
KDIR := /home/_Jana/linux-2.6.38
all:
make -C $(KDIR) M=$(PWD) modules ARCH=arm CROSS_COMPILE=arm-linux-
clean:
rm -f *.ko *.o *.mod.o *.mod.c *.symvers *.order
endif
2、实验结果