android源码编译之06XXXServicesFramework编写之可行性试验03硬件抽象层(HAL)及硬件服务接口

1,增加硬件抽象层(HAL)模块访问linux内核驱动程序
①创建相关文件

1. senrsl@senrsl-ubuntu:~$ cd android/source/WORKING_DIRECTORY/
2. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY$ cd hardware/libhardware/include/hardware/
3. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/include/hardware$ vi senrsl.h
4. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/include/hardware$ cd ..
5. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/include$ cd ..
6. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware$ cd modules/
7. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/modules$ mkdir senrsl
8. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/modules$ cd senrsl/
9. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/modules/senrsl$ touch senrsl.c
10. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/modules/senrsl$ gedit senrsl.c
11. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/modules/senrsl$ touch Android.mk
12. senrsl@senrsl-ubuntu:~/android/source/WORKING_DIRECTORY/hardware/libhardware/modules/senrsl$

1)/home/senrsl/android/source/WORKING_DIRECTORY/hardware/libhardware/include/hardware/senrsl.h

1. /**
2. * 这里按照Android硬件抽象层规范的要求，分别定义模块ID、模块结构体以及硬件接口结构体。在硬件接口结构体中，fd表示设备文件描述符，对应我们 将要处理的设备文件"/dev/senrsl"，set_val和get_val为该HAL对上提供的函数接口。
3. */
4. #ifndef ANDROID_SENRSL_INTERFACE_H
5. #define ANDROID_SENRSL_INTERFACE_H
6. #include <hardware/hardware.h>
7. __BEGIN_DECLS
8. /*定义模块ID*/
9. #define SENRSL_HARDWARE_MODULE_ID "senrsl"
10. /*硬件模块结构体*/
11. struct senrsl_module_t {
12.     struct hw_module_t common;
13. };
14. /*硬件接口结构体*/
15. struct senrsl_device_t {
16.     struct hw_device_t common;
17.     int fd;
18.     int (*set_val)(struct senrsl_device_t* dev, int val);
19.     int (*get_val)(struct senrsl_device_t* dev, int* val);
20. };
21. __END_DECLS