A Device Driver is one of the most discussed words in the computer world. Sometimes you buy a new device, like a keyboard from a new company or a gaming joystick, you might face a problem connecting it to your computer. The reason for not connecting with your computer is that your OS doesn’t have suitable drivers to communicate with this new device.
This tutorial will explain the device drivers, their importance, and use cases in simple words. So, even a guy with little technical knowledge about computers can understand the concept well.
What are Device Drivers?
Every computer has an Operating System (OS) like windows, Linux, or MACOS. This operating OS helps you run different applications on your computer.
Suppose you want to play a video, you just click your favorite video, and it displays on your screen. That’s the software side of OS.
What if your computer wants to communicate with external hardware like a keyboard, mouse, joystick, or even headphones? How will your OS know what type of data this external device sends to your computer, as it is not part of your computer?
Let’s take the example of the keyboard. You press the button on the keyboard; it sends some data to the computer. Your computer doesn’t know the type of data and other communication requirements coming from the keyboard.
This is where the device driver finds its importance. It is a program that tells the OS about the external device. It tells the computer about the type of data that should be sent by the external device (in our case, its keyboard), at which speed it will send data, and how to send data from the computer to the keyboard.
So, in simple words, device drivers act as the middleman between the operating system and external devices. It contains protocol information and communication ways to interact with external devices.
Now we guess you are ready to see the formal definition of device drivers.
“ A device driver is a special kind of code that controls external hardware devices attached to a computer. This program ensures proper communication of external devices to your computer. ”
What Happens If Devices Drivers are Not Present?
If you buy a new computer hardware accessories and its device driver is not present in your operating system, your computer accessory will not work.
You must be thinking that this hardware is a complete waste of money. It is not working with your OS. If you think so, please calm down. Almost every hardware vendor provides device drivers to connect their devices to the computers. You can simply google and install the drivers of your accessory in your OS if it is not already present.
Device drivers are OS dependent. If you are manually installing device drivers for any external hardware, you should ensure that you are installing the right drivers, compatible with your OS. You will easily find a lot of tutorials on installing device drivers in different operating systems like Linux, Windows and MacOS.
How Device Driver Works?
Each operating system (OS) has a piece of code for implementing its core functionality. This piece of code in OS is called Kernel. It is the main interface between your computers physical hardware and the processes running on it. It is responsible for sharing hardware resources of computer by providing access to central processing unit (CPU), memory, IO pins and networking.
Device drivers resides in this kernel code. As kernel has low-level access to computer resources, therefore the device drivers can easily perform direct operation with computer hardware. In this way, device drivers make it possible to communicate with external devices easily.
Once you have installed the driver in your computer for particular hardware, you can easily interact with that hardware. You will simply send a command from some graphical (GUI) application or command. Your device driver will see that command, communicate with that hardware using low-level API’s and send your response back.
That simple. Isn’t it? We hope that this simple explanation will clear all your doubts about device driver working.
Can You Write Your Own Device Driver?
Many people ask that whether its possible to write device driver for any hardware. Yes, you can write a device driver for any device if you know programming. Linux device drivers are written in C programming language. However, you should have a complete understanding of hardware and strong grip on kernel C programming to write your own device driver.
The better way is to find the driver for your hardware on google. If you don’t find the driver on google, simply contact the hardware vendor to provide you the device driver. They will most probably help you in integrating driver for their hardware in your OS.
Final Words:
That’s all from our side today. We tried our best to explain the concept and working of device driver in simplest possible words. We will cover the advance concepts about the device drivers in the upcoming blogs soon. So stay connected with us to learn about device drivers and other Embedded Linux concepts.