1. 创建目录
	cd  hardware/interfaces
	mkdir -p yetest/1.0
2. 定义hal接口IYetest.hal
	package android.hardware.yetest@1.0;
	interface IYetest {
	    setData(YeData data) generates (YeStatus ret);
	    getData() generates (YeData ret);
	};
3. 根据.hal自动生成impl库的cpp实现
	在hardware/interfaces/yetest/1.0目录执行hidl-gen命令：
	PACKAGE=android.hardware.yetest@1.0
	LOC= default/impl
	hidl-gen -o $LOC -Lc++-impl -r android.hardware:hardware/interfaces $PACKAGE 
4. 生成impl的Android.bp
	hidl-gen -o default -Landroidbp-impl -r android.hardware:hardware/interfaces $PACKAGE
5. 生成hidl的Android.bp
	执行hardware/interfaces/update-makefiles.sh
6. 修改device/fsl/imx8q/XXX/manifest.xml
	添加以下代码：
	    <hal format="hidl">
	        <name>android.hardware.yetest</name>
	        <transport>hwbinder</transport>
	        <version>1.0</version>
	        <interface>
	            <name>IYetest</name>
	            <instance>default</instance>
	        </interface>
	    </hal>
7. 编写.rc文件
	配置自启动
	service vendor.yetest-1.0 /vendor/bin/hw/android.hardware.yetest@1.0-service
	    class hal
	    user system
	    group system
8. 添加PRODUCT_PACKAGES
	在device/fsl/imx8q/XXX/XXX.mk中新增
	打包.so和service到vendor.img
	# Yetest HAL
	PRODUCT_PACKAGES += \
	     android.hardware.yetest@1.0-impl \
	     android.hardware.yetest@1.0-service
9. device/fsl/imx8q/XXX/BoardConfig.mk中指定sepolicy路径：
	BOARD_SEPOLICY_DIRS +=  hardware/interfaces/yetest/sepolicy
10. 在hardware/interfaces/yetest/sepolicy目录新增yetest.te:
	type yetest, domain;
		
	type yetest_exec, exec_type, vendor_file_type, file_type;
	hwbinder_use(yetest);
	init_daemon_domain(yetest)
	add_hwservice(yetest,yetest_hwservice)
		
	allow yetest hwservicemanager_prop:file {read open getattr map};
	allow yetest system_file:dir {read open getattr search};
11. hardware/interfaces/yetest/sepolicy目录下新增file_contexts:
	绑定android.hardware.yetest@1.0-service与yetest_exec的关系的关键
	/(vendor|system/vendor)/bin/hw/android\.hardware\.yetest@1\.0-service    u:object_r:yetest_exec:s0
	/(vendor|system/vendor)/lib(64)?/hw/android\.hardware\.yetest@1\.0-impl\.so     u:object_r:same_process_hal_file:s0
12. 新增harware/interfaces/yetest/sepolicy/hwservice_contexts:
	android.hardware.yetest::IYetest u:object_r:yetest_hwservice:s0
13. 新增harware/interfaces/yetest/sepolicy/hwservice.te:
    type yetest_hwservice, hwservice_manager_type;