The Generic Driver Framework Design Of USB Wireless Network Adapter Based On Linux

The Linux operating system is one leader in open source world.Linux is the best choicefor embedded projects that just because Linux is open source. To go through the purchase ofhardware in a typical embedded project, the production of circuit boards, cutting a suitableoperating system, add the process of application layer software. Want to choose a suitableoperating system on the basis of certain characteristics of the hardware, if the operatingsystem is closed that the difficulty can be imagined. Linux operating system supports manyUSB wireless card. Each Wireless card has it’s own driver, these drivers have the same orsimilar point from functions,responsibilities,the interface called and service agreements. Whynot to summarize the same point, and deal with their differences to design a USB wirelesscard generic driver?I must mention the driver in the process of cutting the Linux operating system whichmaking it support special hardware. In an embedded project which will often encountercertain hardware can not work, if do not know the driver’s knowledge at this time, theproblem will become very difficult. Driver source code occupy the largest proportion of theamount of code in the Linux operating system kernel. Therefore, the driver’s knowledge isvery worth to study. The purpose of this paper is to design generic driver framework programunder in-depth study Linux USB wireless network card drivers, which using software reuseand software layered technology to together the various types of USB wireless network carddriver, The generic driver framework program also can be used as ieee802.11an extension ofthe agreement in the driver layer. The various types of USB wireless network card puts thedifferences processing into the parameter file in user space. When need one network carddriver, the generic driver framework program reads the wireless card’s hardware parameterfile and dynamic composition of the network card driver. In this article, this process is that thesystem calls the generic driver framework program when a USB wireless card plugged intothe USB interface, the generic driver framework program goes to a specified path directory tofinds the parameter file of the hardware and reads the parameter file,generates thecorresponding parameter chain, then the generic driver framework chang into a proprietarydriver for this hardware. This whole process is similar to the driver to find the firmware, theprocess of looking for the firmware is also the first in the specified path directory to findfirmware, and then read into the hardware chip, only the firmware is compiled device chip toexecute instructions. If set up the driver accordance with this way, then the parameters in the parameter chain to be able to handle all the differences of their own hardware. This articledesign parameters data structure which in the parameter chain, design a parameter calculatorin the core part of the processing parameters, and seal the package several interface functionsof the drive communicate to USB devices. Parameter processing section also defines theparameters from and whereabouts.In this way to design the driver, then the proportion of the driver’s source code will begreatly reduced. And USB wireless network card in this article the generic driver frameworkprogram has matured, the preparation work of the USB wireless network card driver into thepreparation of the network card in the user space hardware parameter file. This paper selectedtwo different types of USB wireless card to test the effect of the generic driver framework,and test a network card working conditions, the driver works normal. In line with the originalintention of the original design.