Design And Implementation Of Bottom-layer Software For Several I2C-based Sensors In Android Operating System

Since the release of its first version in2008by Google Cor., Android has nowbecome the most popular smart phone operating system, and has taken the biggest partof the smart phone market share. Applying several kinds of sensors in Android smartphone not only saves the power consumption of an Android smart phone, but alsoenriches its functionality. So, only with a thorough grasp of sensor related bottom-layersoftware development technology in Android system, can we develop an Android smartphone with greater performance.By participating in the whole development process of TD920Android smart phone,this paper devises and implements the driver and hardware abstract layer software forlight sensor, proximity sensor and acceleration sensor in Android system. First of all, wemake a research on the principle of Android operating system and several differentkinds of Android developing jobs, and make it clear which layer this paper’s research isat and what our devising and implementing tasks are. Then, we carry on the preliminarydesign for sensor driver and hardware abstract layer software, and divide ourbottom-layer software into several modules according to their difference in functionality,they are: I2C driver module, the configuration of AL3003and BMA220module,character device driver module, management of sensors through Linux Sysfs systemmodule, data report through Linux input sub-system module. Also, the work flow, dataobtain and data transformation at hardware abstract layer is designed. Followed, wecarry on the design and implement of these modules in detail.By developing and testing under the software and hardware platform provided byTD920Android smart phone, we confirm the feasibility and effectiveness of the design.