Chapter 15: Distributing Device Drivers

Chapter 15

Distributing Device Drivers

Early in the device driver development process, it s important to devote some thought to how you ll distribute your driver and how an end user will install your driver and the hardware it serves. MicrosoftWindows XP and Microsoft Windows 98/Me use a text file with the file extension INF to control most of the activities associated with installing drivers. You provide the INF file. It goes either on a diskette or on a disc that you package with the hardware, or else Microsoft makes it available on line or on a setup disc. In the INF file, you tell the operating system which file or files to copy onto the end user s hard disk, which registry entries to add or modify, and so on.

In this chapter, I ll discuss several aspects of installing your driver. I ll discuss the important role played by the registry in driver installation and initialization. I ll lead you through the important parts of a simple INF file to help you tie together the DDK documentation about INF file syntax. I ll explain in detail the format of device identifiers used for various types of devices. Since I had to define a custom device class for all the sample devices used in this book, I thought it would help you to see how I did that.

Microsoft operates the Windows Hardware Quality Lab (WHQL) to help ensure the quality of the hardware and device drivers that end users purchase for use with Windows operating systems. WHQL provides a Hardware Compatibility Test kit (HCT) for use with many common classes of device. You should aim to pass these tests to qualify for Microsoft s logo licensing programs and to obtain a digital signature file that will greatly simplify installation on end user machines. I ll guide you through the process of putting together a WHQL submission in this chapter.