Design And Implementation Of MIPI Device Driver Based On Android

With the progress of technology and the continuous improvement of people’s living standard, people are becoming inseparable from the mobile devices day by day. Mobile phone and tablet as the important carrier of the Android system has entered every household. Android is one kind of embedded operating system taking the largest market share, which is most different from Symbian, iOS, Windows Mobile, blackberry systems for its characteristics of open, free and simple. Therefore, Android is chosen as the carrier of research object in this thesis.MIPI (Mobile Industry Processor Interface) is not only an alliance but also a kind of interface technology. It’s the latest interface technology for mobile application processor interface. MIPI, however, is not a single interface and protocol, but a set of Interface standards. Now DSI (Display Serial Interface) and CSI2(Camera Serial Interface2) have been applied for practice making very good effect, the other protocols still be in develop and perfect. At the same time, DSI and CSI2are also developing to a higher version. Based on practical application, the Android system architecture has been studied in this thesis; At the same time, detail research has been made respectively for MIPI-DSI and MIPI-CSI2, and Ubuntu system is used for MIPI driver program design, compile and debug; and then LCD module and Camera module of the smartphone are respectively controlled by MIPI-DSI and MIPI-CSI2;Finally the MTK smartphone platform is used to validate the result of the design. The experiment results of LCD module and Camera module prove that MIPI technology still achieves excellent performance in anti-interference ability, speed, stability while reducing volume, power dissipation and lower cost, which is the development direction of mobile interface technology.This paper mainly complete the following work:First, the background and significance of MIPI, the present situation of Android development and MIPI development are studied, and the structure of this paper are generalized.Secondly, the basic framework of the Android platform and the Android kernel feature are studied, and the hierarchical analysis is made. Third, the protocol specification of MIPI DSI and CSI2are researched in detail and the relationship between layer and layer of DSI/CSI2is researched.Fourth, the hardware test platform and Android development environment used in this paper are introduced.Fifth, MIPI-DSI device driver is designed and debugged in Ubuntu10.04system, to control the LCD module, and the MTK smartphone platform is used to verify. LCD screen with480x854resolution is lighted up by two lanes in total6pins, the clock frequency is234MHZ, the screen refresh rate is greater than60FPS, which gets the desired effect, which gets outstanding performance for MIPI.Sixth, MIPI-CSI2device driver is designed and debugged in Ubuntu10.04system, to control the Camera module, and the MTK smartphone platform is used to verify. The5M megapixel Camera is lighted up with two lane in total6pins, clock frequency is336MHZ,1280x720resolution video recording reaches30FPS, which gets outstanding performance for MIPI.Finally, summarize the full work and subsequent work in the future.