TQ210搭载Android4.0.3系统构建之ADC从驱动到HAL到JNI到应用程序(JNI篇)

#include <android/log.h>
#include <jni.h>
#include <hardware/hardware.h>
#include <hardware/adc_under_hal.h>

static struct adc_hw_device_t *adc_device=NULL;

#define true 1
#define false 0

static inline int adc_open(struct hw_module_t *module,struct adc_hw_device_t **device) //adc打开函数，获取到设备给adc_device
{
int ret=module->methods->open(module,ADC_UNDER_ID,(struct hw_device_t **)device);
if(ret!=0) __android_log_print(ANDROID_LOG_DEBUG,"msg", "can not open adc_open in jni.\n");
return ret;
}

jint Java_com_under_adc_AdcActivity_adcRead(JNIEnv * env, jclass clazz) //读取adc的值
{
if(adc_device==NULL) return false;
return adc_device->read(adc_device);
}

jboolean Java_com_under_adc_AdcActivity_adcClose(JNIEnv * env, jclass clazz) //adc 关闭函数
{
if(adc_device==NULL) return false;
return adc_device->common.close(&adc_device->common);
}

jboolean Java_com_under_adc_AdcActivity_adcInit(JNIEnv *env,jclass clazz)  //adc 初始胡函数，通过此函数获取到jni层的模块
{
struct adc_hw_module_t *module;
int ret=hw_get_module(ADC_UNDER_ID, (const struct hw_module_t **)&module); //通过ID获取到jni层的模块
if(ret==0)
{
if(adc_open(&module->common,&adc_device)==0) return true;
}
__android_log_print(ANDROID_LOG_DEBUG, "msg","adcInit failed.\n");
return false;
}

LOCAL_PATH :=$(call my-dir)
include $(CLEAR_VARS)
LOCAL_PRELINK_MODULE :=false
LOCAL_SHARED_LIBRARIES :=libutils \
libhardware
LOCAL_SRC_FILES  :=adc_under_jni.c
LOCAL_MODULE  :=libadcunders
LOCAL_MODULE_PATH :=$(LOCAL_PATH)
LOCAL_MODULE_TAGS :=optional
include $(BUILD_SHARED_LIBRARY)