Last updated on 2024年6月5日

How can you design and implement device drivers like a pro?

由人工智能和领英社区提供技术支持

Device drivers are software components that allow the operating system to communicate with hardware devices, such as keyboards, mice, printers, scanners, cameras, disks, network cards, and so on. They are essential for the functionality and performance of any computer system, but they also pose many challenges and risks for the developers who design and implement them. In this article, you will learn some tips and best practices on how to create device drivers like a pro, based on the principles of operating system concepts.

此文章中的业界达人

由社区从 5 条内容中精选。了解更多

Gautam Shiroor

Principal Firmware Engineer at Western Digital

1 Understand the device and the interface

The first step in designing a device driver is to understand the characteristics and capabilities of the device that you want to support, and the interface that it uses to communicate with the system. Different devices have different types of interfaces, such as memory-mapped I/O, port-mapped I/O, direct memory access (DMA), interrupts, or bus protocols. You need to know how to access the device registers, how to read and write data, how to handle errors and status changes, and how to configure and control the device. You also need to know the device specifications, such as the data format, the timing, the power consumption, and the compatibility issues.

添加您的观点

Madhavan Vivekanandan

Senior Technical Architect at HCL America
举报内容
The first step in designing a device driver is to understand the characteristics and capabilities of the device that you want to support, and the interface that it uses to communicate with the system. This includes understanding the following: What type of device is it? (e.g., network card, storage device, printer, etc.) How does it communicate with the system? (e.g., memory-mapped I/O, port-mapped I/O, direct memory access (DMA), interrupts, or bus protocols) What are its registers and how are they used? What commands does it support? What data structures does it use? What are its performance and reliability characteristics?

已翻译

赞

2 Choose the right driver model and framework

The next step is to choose the appropriate driver model and framework for your device driver, depending on the operating system that you are targeting, the type and complexity of the device, and the level of abstraction that you want to provide. Different operating systems have different driver models and frameworks, such as Windows Driver Model (WDM), Windows Driver Foundation (WDF), Linux Device Model (LDM), Linux Kernel Module (LKM), or Device Driver Kit (DDK). These models and frameworks provide various features and services, such as device enumeration, plug-and-play support, power management, security, debugging, testing, and documentation. You need to understand the advantages and disadvantages of each model and framework, and how to use them effectively.

添加您的观点

Madhavan Vivekanandan

Senior Technical Architect at HCL America
举报内容
Linux driver model is based on a few key concepts: Bus types: Bus types represent different ways of connecting devices to the system, such as PCI, USB, and I2C. Each bus type has its own driver model, which is responsible for enumerating devices on the bus and managing their resources. Device drivers: Device drivers are specific to a particular type of device. They provide the kernel with the information it needs to use the device, such as its memory addresses, interrupt lines, and power management requirements. Device model: The device model is a generic representation of a device. It provides a common interface for device drivers to interact with the kernel, regardless of the type of bus the device is connected to.

已翻译

赞

3 Design the driver architecture and interface

The third step is to design the architecture and interface of your device driver, based on the requirements and specifications of the device, the driver model and framework, and the user applications that will use the driver. You need to decide how to structure your driver code, how to organize your files and directories, how to name your variables and functions, and how to document your code. You also need to design the interface that your driver will expose to the system and the user applications, such as the device name, the device class, the device file, the device node, the device object, or the device handle. You need to define the operations that your driver will support, such as open, close, read, write, ioctl, or mmap, and the parameters and return values that they will use.

添加您的观点

4 Implement the driver functionality and logic

The fourth step is to implement the functionality and logic of your device driver, using a programming language and tools that are suitable for the driver model and framework, such as C, C++, Assembly, Visual Studio, Eclipse, or GNU Compiler Collection (GCC). This requires writing code to initialize and deinitialize the driver and the device, such as loading and unloading the driver module, registering and unregistering the driver with the system, allocating and freeing the device resources, and setting and resetting the device state. Additionally, you need to handle the device requests and events by processing device operations, transferring data between the device and system, managing queues and buffers, and responding to interrupts and signals. Lastly, you should implement driver logic and algorithms by validating input/output data, encoding/decoding data, controlling device modes/settings, as well as performing any device-specific functions or calculations.

添加您的观点

Gautam Shiroor

Principal Firmware Engineer at Western Digital
举报内容
Do not use undocumented/deprecated kernel interfaces. Using well documented and supported kernel API's will go a long way in supporting future releases of the OS.

已翻译

赞
Girish Handral
举报内容
-Have an outline of upper or use mode app interface apis: control, config and data modes - wrap all operations that need to be performed on the device or h/w interface. - get these two reviewed with apps team and h/w team - write down design objectives for internal operations for the driver itself: I/O queues, memory/buffer/packet management, interrupt scheme, protocol details or algorithm details etc. - document test function objectives for interface apis, driver apis, functional test cases.

已翻译

赞

5 Test and debug the driver code and behavior

The fifth step is to test and debug the driver code and behavior, using the tools and methods that are available for your driver model and framework, such as breakpoints, watchpoints, tracepoints, logs, messages, assertions, or kernel debuggers. You need to verify that your driver code is correct, consistent, and compliant with the coding standards and conventions. You also need to check that your driver behavior is reliable, efficient, and compatible with the device, the system, and the user applications. You need to identify and fix any errors, bugs, or issues that may occur in your driver, such as memory leaks, buffer overflows, deadlock, race conditions, or device conflicts.

添加您的观点

Madhavan Vivekanandan

Senior Technical Architect at HCL America
举报内容
Some additional tips for debugging device drivers: Use a debugger. A debugger allows you to step through the driver's code line by line, and to inspect the values of variables. Use breakpoints. Breakpoints allow you to stop the driver's execution at a specific point in the code. Use watchpoints. Watchpoints allow you to monitor the values of specific variables. If the value of a variable changes, the debugger will stop the driver's execution. Use logging. You can use logging to log the values of variables, the events that occur in the driver, and the errors that are encountered. Use analysis tools. These tools can analyze the driver's code, the driver's execution, and the system's state.

已翻译

赞

6 Optimize and improve the driver performance and quality

The sixth step is to optimize and improve the driver performance and quality, using the tools and techniques that are suitable for your driver model and framework, such as profilers, analyzers, benchmarks, or quality metrics. You need to measure and evaluate the performance and quality of your driver, such as the speed, throughput, latency, accuracy, or robustness. You also need to find and implement ways to improve the performance and quality of your driver, such as reducing the overhead, increasing the concurrency, enhancing the scalability, or adding the features and functionality.

添加您的观点

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?

添加您的观点

Operating Systems

+ 关注

给文章评分

我们借助人工智能创建了此文章。您认为这篇文章怎么样？

很棒不太好

举报此文章

查看全部

How can you design and implement device drivers like a pro?

1

2

3

4

5

6

7

1 Understand the device and the interface

2 Choose the right driver model and framework

3 Design the driver architecture and interface

4 Implement the driver functionality and logic

5 Test and debug the driver code and behavior

6 Optimize and improve the driver performance and quality

7 Here’s what else to consider

Operating Systems

给文章评分

感谢您的反馈

更多Operating Systems相关文章

更多相关阅读内容

How can you design and implement device drivers like a pro?

1

2

3

4

5

6

7

1 Understand the device and the interface

2 Choose the right driver model and framework

3 Design the driver architecture and interface

4 Implement the driver functionality and logic

5 Test and debug the driver code and behavior

6 Optimize and improve the driver performance and quality

7 Here’s what else to consider

Operating Systems

给文章评分

感谢您的反馈

查看其他技能