Android驱动入门-Led控制+app+ndk库+底层驱动

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.zws.test_led.MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"> <LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal">
<CheckBox
android:id="@+id/checkbox_cmd_led1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Led1"/> <!--id在判断复选框状态时使用--> <CheckBox
android:id="@+id/checkbox_cmd_led2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Led2"/> <CheckBox
android:id="@+id/checkbox_cmd_led3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Led3"/> <CheckBox
android:id="@+id/checkbox_cmd_led4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Led4"/>
</LinearLayout>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="发送命令"
android:onClick="on_click_cmd"/> <!--按钮响应函数名称-->
</LinearLayout></RelativeLayout>

package com.example.zws.test_led;import android.app.Activity; //可更改
import android.os.Bundle;
import android.view.View;
import android.widget.CheckBox;import java.util.zip.CheckedInputStream;public class MainActivity extends Activity { //需和import android.app.Activity;一致 private CheckBox[] cbCmdLeds = new CheckBox[4]; //创建按钮数组
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); cbCmdLeds[0] = (CheckBox)findViewById(R.id.checkbox_cmd_led1); //需要强制转化
cbCmdLeds[1] = (CheckBox)findViewById(R.id.checkbox_cmd_led2);
cbCmdLeds[2] = (CheckBox)findViewById(R.id.checkbox_cmd_led3);
cbCmdLeds[3] = (CheckBox)findViewById(R.id.checkbox_cmd_led4);
} public void on_click_cmd( View view )
{
for( int i=0; i<4; i++ )
{
if( cbCmdLeds[i].isChecked() ) //如复选框被选中
CmdLeds( 1,i ); //此函数在下面有声明。
else
CmdLeds( 0,i );
}
} public native void CmdLeds( int cmd, int arg ); //需要调用的外部函数可自己设定 static
{
System.loadLibrary("ndk_test_myled"); //外部库的名称，可自己设定
}
}

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/cdev.h>MODULE_LICENSE("GPL");#define GPM4CON 0X110002E0//io口控制寄存器硬件地址
#define GPM4DAT 0X110002E4//io口数据寄存器硬件地址#define LED_ON _IOW('G',0,int)//打开命令#define LED_OFF _IOW('G',1,int)//关闭命令static struct cdev dev;//1.1 分配cdev结构static dev_t dev_no;//设备号
struct class *led_class;static unsigned int *led_con;
static unsigned int *led_dat;long led_ioctl( struct file *file, unsigned int cmd, unsigned long arg )
{
switch( cmd )
{
case LED_ON:
writel((readl(led_dat)&(~(0x1<<(arg-)))),led_dat);
break; case LED_OFF:
writel( (readl(led_dat)|(0x1<<(arg-))),led_dat);
break; default:
return -EINVAL;
break;
}
return ;
}struct file_operations led_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = led_ioctl,
};static void hw_init()
{ //初始化GPIO控制寄存器
led_con = ioremap( GPM4CON, ); //地址映射 将实际的硬件地址映射成可访问的虚拟地址
led_dat = ioremap( GPM4DAT, );
writel((readl(led_con)&~0xffff)|0x1111,led_con);
writel(readl(led_dat)|0xf,led_dat); }static int led_init()
{ //1.2 初始化cdev结构
alloc_chrdev_region( &dev_no, , , "my_led" );
cdev_init( &dev, &led_fops );
dev.owner = THIS_MODULE;
//1.3 注册cdev结构
cdev_add( &dev, dev_no, );
//2.硬件初始化
hw_init();
//3.创建设备文件
led_class = class_create(THIS_MODULE,"my_led"); //创建设备类
device_create( led_class, NULL, dev_no,NULL,"%s","my_led");// 创建设备文件 my_led printk("init led device ok!\n"); return ;
}void led_exit()
{
device_destroy(led_class,dev_no);
class_destroy(led_class); iounmap(led_con);
iounmap(led_dat); cdev_del(&dev);
unregister_chrdev_region(dev_no,);
}module_init( led_init );
module_exit( led_exit );

obj-m := led.o
KDIR := /home/share/linux-3.0.86//内核地址all:
make -C $(KDIR) M=$(PWD) modules CROSS_COMPILE=arm-linux- ARCH=arm
clean:
rm -f *.ko *.o

adb push led.ko /data/local/

javah -d jni -classpath /opt/android-sdk-linux/platforms/android-/android.jar:/home/my_Android/led\
/NDK/NDK_APP/app/build/intermediates/classes/debug/ com.android.jack.ndk.happy.MainActivity

#include "com_example_zws_test_led_MainActivity.h"//生成的头文件#include <jni.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <stdlib.h>#define LED_ON _IOW('G',0,int)
#define LED_OFF _IOW('G',1,int)JNIEXPORT void JNICALL Java_com_example_zws_test_1led_MainActivity_CmdLeds
(JNIEnv *env, jobject this, jint cmd, jint arg)//头文件中的接口函数 此函数名称为系统自动生成的 勿修改。
{
int fd;
int tmp_cmd; fd = open("/dev/my_led",O_WRONLY);//此为在写驱动程序时，生成的设备文件名称 if( cmd == )
tmp_cmd = LED_ON;
else if(cmd==)
tmp_cmd = LED_OFF; ioctl(fd,tmp_cmd,arg+);
close(fd);
}

LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := ndk_test_myled //这个是库的名称 可自己设定
LOCAL_SRC_FILES := ndk_led.c//之前写的c文件名称
include $(BUILD_SHARED_LIBRARY)

ndk-build

$ su
$ insmod /data/local/led.ko
$ chmod /dev/my_led