Design And Implementation Of Linux Audio System Driver In Communication And Navigation Integration Chip

With the rapid advance of information science and technology and the improvement of our living standard,communication technology has been used more and more widely,and communication equipment has a more and more important effect on our life. Smart terminal has been a necessary communication tool in people’s life.The paper is based on the communication and navigation integration program at a company of Shanghai,and the chip to be developed is primarily used on intelligent terminal.With the degree of dependence on the mobile devices(such as mobile phone,tablet pc and so on)deepening,human-computer interaction is more important.In the meantime,with the rise of social platform,such as Fetion and WeChat and so on, all of these platforms include voice function,which is based upon audio processing technology.So high quality voice is the guarantee of effective communication. While the realization of the high quality speech is based on the audio driver technology,and only good audio driver is designed,can make the audio devices work effectively.The paper primarily introduces some relevant theoretical knowledge,including A/D conversion,audio bus format,Linux device driver model and Linux audio architecture and so on.And Linux audio architecture includes ALSA audio driver structure which is applied in Linux,DMA,IIS bus interface and IIC bus interface.Then,the paper describes communication and navigation integration chip and analyzes Linux audio system driver function and chooses architecture ASoC,and then realizes the whole design of the driver.Moreover,the paper designs modules of Linux audio system driver,including platform driver,Codec driver and machine driver.Machine driver registers sound card and initializes ASoC,and Codec driver registers and initializes Codec and codec_dai,and platform driver implements DMA and cpu_dai driver.The end of the paper is about the system’s software environment and hardware environment and its test.