基于MIPI接口的Android显示驱动设计

Design of Android Display Driver Based on MIPI Interface

针对现有RGB(Red Green Blue)显示接口与LVDS(Low Voltage Differential Singnaling)显示接口无法满足嵌入式高清显示需求的问题,在Arm架构的RK3288目标系统上开发了MIPI(Mobile Industry Processor Interface)接口显示驱动。笔者首先分析了MIPI架构,整理了MIPI四层架构的任务划分,进而研究了Android整个显示机制的工作流程,将驱动开发任务锁定在内核层,最后分别在U-boot阶段和Kernel阶段编写显示驱动,U-boot阶段负责开机Logo显示,Kernel阶段负责主界面显示。系统的运行情况表明,显示驱动编写正确,显示功能正常。

Aiming at the problem that the existing RGB(red green blue)display interface and LVDS(low voltage differential singling)display interface can not meet the requirements of embedded HD display,Mipi(mobile industry processor interface)display driver is developed on the rk3288 target system of arm architecture.Firstly,the author analyzes the Mipi architecture,sorts out the task division of Mipi four layer architecture,and then studies the workflow of the entire display mechanism of Android.The driver development task is locked in the kernel layer.Finally,the display driver is written in the u-boot stage and the kernel stage respectively.The u-boot stage is responsible for the startup logo display,and the kernel stage is responsible for the main interface display.The operation of the system shows that the display driver is programmed correctly and the display function is normal.