Android from hardware to application: Step by Step 2, step by step android

Android from hardware to application: Step by Step 2, step by step android

Compile a C program to quickly test the hardware driver:

Create the driver_test folder in the external Folder under the root directory of the Android source code:

Cd external

Mkdir driver_test

Cd driver_test

Create Android. mk:

LOCAL_PATH := $(call my-dir)include $(CLEAR_VARS)LOCAL_MODULE_TAGS := optionalLOCAL_MODULE := driver_testLOCAL_SRC_FILES := driver_test.cinclude $(BUILD_EXECUTABLE)

Create driver_test.c:

#include <stdio.h>  #include <stdlib.h>  #include <fcntl.h>        int main(int argc, char *argv[])  {      int  fd;      int  val=0;        fd=open("/dev/AdrIO",O_RDWR);            if(fd<0)      {          printf("open device failed !\n");          exit(1);      }      else      {          printf("open success ! \n");      }              write(fd,argv[1],1);                close(fd);      return 0;  }  

Go back to the Android source code root directory: make driver_test

An error may be prompted at first:

Host c ++: libhost <= build/libs/host/pseudo dolocalize. cpp/bin/bash: g ++: Command not found

Make: *** [out/host/linux-x86/obj/STATIC_LIBRARIES/libhost_intermediates/pseudo localize. o] Error 127

Solution:

Sudo-I
Aptitude install g ++

Sudo apt-get install build-essential

After installation, run make driver_test.

The final compilation is complete:

Install: out/target/product/generic/system/lib/libm.soInstall: out/target/product/generic/system/bin/driver_test

Copy out/target/product/generic/system/bin/driver_test to the AM335X file system and start Android

Run:

./Driver_test 1 (D1 on at this moment)

./Driver_test 0 (D1 off at this time)

The test is successful. You can use this method to quickly test the Linux kernel driver in android.