基于ARM的平板电脑的底层硬件驱动设计

摘要I摘要推出平板的目的是为了弥补手机和笔记本电脑之间的这块空白区域，就是为人们提供一款和手机一样携带方便、操作简单，但比手机视觉效果更好，并能像笔记本电脑一样可以快速流畅的上网、观看视频和玩游戏的产品。软件方面，除苹果自己有自己的IOS外，不管是国内还是国外厂商，由于google的开源，基本都选择了andriod操作系统作为开发平台。Android是一个基于linux内核的操作系统，在一款产品的开发过程中，硬件驱动程序的开发和调试是一项艰巨的任务，驱动程序的质量直接影响产品的性能和稳定性，所以对平板上驱动程序的研究和设计具有实际工程意义。此次设计针对平板电脑中常用的几个硬件驱动进行了研究和设计，如LCD驱动，PWM背光驱动，按键驱动等。旨在熟悉驱动设计流程，掌握驱动设计的一般方法。关键字：平板电脑,Android,linux，硬件驱动ABSTRACTIIABSTRACTThepurposeofthelaunchofthetabletisinordertomakeupthepieceofblankareabetweenmobilephonesandlaptopcomputersforpeopletoofferadeviceaseasyasmobilephonetocarry,simpletooperate,butbetterthanthemobilephonevisualeffects,andthesameasthelaptopcanquicklyaccesstotheInternet,watchingvideosandplayinggames.Onthesoftwareside,inadditiontoApple'sownIOS,whetherdomesticorforeignmanufacturers,becauseofgoogleopenedtheandroidsourcecode,basicallychoosetheandriodoperatingsystemasthedevelopmentplatform.AndroidisaLinuxkernel-basedoperatingsystem,intheprocessofaproductdevelopment,developinganddebugginghardwaredriversisanarduoustask,thequalityofthedriverdirectlyimpactonproductperformanceandstability,SotheresearchanddesignofthedriverontheTabletPChasapracticalengineeringsignificance.ThispaperwillresearchanddesignafewhardwaredriversthatcommonlyusedintheTabletPC,suchasLCDdrivers,PWMbacklightdriver,keydriversandsoon.Thepurposeofthisdesignistofamiliartothedriverdesignprocessandgraspthegeneralapproachtodriverdesign.Keywords:tabletpc,android,linux,hardwaredrivers目录III目录第一章引言..................................................................................................................51.1ARM处理器介绍................................................................................................51.2android操作系统介绍........................................................................................61.3平板电脑驱动开发概述......................................................................................7第二章软硬件平台介绍和启动过程分析..............................................................92.1硬件平台介绍.........................................................................................................92.2软件平台介绍.........................................................................................................92.3启动过程分析.......................................................................................................10第三章LCD驱动设计及实现...................................................................................133.1显示控制器及显示器硬件配置...........................................................................133.1.1S5PV210显示控制器.......................................................................................133.1.2三星9.7寸IPS屏LTN097XL02.....................................................................133.1.3显示模块硬件连接方式....................................................................................143.2android下的LCD驱动........................................................................................153.2.1LCD硬件时序参数设置...................................................................................153.2.2LCD硬件设备注册............................................................................................163.2.3frambuffer驱动注册..........................................................................................18第四章PWM背光驱动设计及实现.........................................................................194.1PWM背光控制器硬件连接...................................................................................194.2linux内核PWM驱动...........................................................................................194.2.1PWM背光设备注册..........................................................................................194.2.2PWM背光驱动注册..........................................................................................204.3PWM背光在androidHAL层移植....................................................................224.3.1什么是硬件抽象层............................................................................................224.3.2HAL的实现机制...............................................................................................23目录IV4.3.3pwm背光的HAL层实现.................................................................................24第五章接键驱动设计及实现....................................................................................275.1接键硬件链接以及功能要求...............................................................................275.2内核空间按键驱动设计和实现............................................................................275.2android对按键的重映射......................................................................................32第六章振动电机驱动设计及实现............................................................................356.1功能要求以及硬件连接........................................................................................356.2内核空间振动电机驱动设计及实现....................................................................356.2.1什么是timedGPIO...........................................................................................356.2.2振动电机的TimedGPIO驱动实现..................................................