Chapter One overview of Android system porting and driver development

The first chapter is to popularize the basic knowledge of Android and Linux to readers .

The first section describes the Android architecture. Android 's system architecture is divided into four tiers:

First layer:Linux kernel. Mainly includes Linux drivers and memory management, process management, power management and other programs. Android uses Linux 2.6 as its kernel.

The second layer:C + + code base. It mainly includes code libraries written in C + + and the runtime of Dalvik VMs.

Third tier:Android SDK API. This layer can also be called the java API layer, which is a variety of Java - based Dalvik virtual machine format Library .

Layer Fourth: Application. All users will be exposed to a layer that is equivalent to the Android UI, and all applications belong to this layer.

The second section describes the main work of Android system porting.

Android migration is divided into application porting (porting the application to a specific hardware platform) and system porting (allowing the android operating system to run on a particular hardware platform, leading to Linux Drive).

Android Migration main work: porting Linux driver, porting HAL.

Section III teaches readers how to query the Linux version.

Method One: Enter uname –a, the output is the Linux kernel version.

Method Two: Input cat/proc/version, the output is the Linux kernel version

The fourth section is the definition rule for the kernel version number.

The Linux kernel version number consists of the major version number, the minor version number, the revision number, the fine-tuning version number, and the description specially tuned for the particular Linux system.

The fifth section describes the steps required to learn about Linux drivers.

Kernel version update faster, only need to master one version, the other is comprehend by analogy.

Mastering the GUN C technology is the most common c language programming environment under Linux.

Test and run on the dev version.

Practice a lot and practise it constantly.

The sixth section describes the development, function, classification and characteristics of Linux device drivers.

Use the driver to abstract the hardware and reduce the degree of coupling.

Drive for memory and peripherals, not for the CPU Core, divided into character devices, block devices, network equipment three categories.

The seventh section shows a driver LED , and so on. Gives the reader A general impression of the Linux driver.

Chapter One overview of Android system porting and driver development