Linux

9. Summary Relationship between 9.1 bus, device, driver and class L bus is equivalent to a container. It is the management mechanism of device and device_driver. It contains a device set (devices_kset) and a driver set (drivers_kset ), indicates

I have been familiar with Wince and Linux for some years. I will make some comparisons based on my recent work experience. 1. Compatibility comparison between wince and Linux Recently I encountered several problems: (1) using the dm3730 core

Input subsystem of Linux driver subsystem (1) 1. Input subsystem framework 1.1 Overview The input subsystem provided by the kernel is a unified processing driver for scattered input devices of different categories (keyboard, mouse, touch screen,

Get what we need from the two tables, and then the following code is expanded around the two pointers. (Unusual_dev and ID) continue to read get_device_info (). Row 3: Record unusual_dev in us. There is also such a member in us. In this way, it will

Error capture in Linux: Use of errno and strerror Some errors often occur when calling Linux system APIs. For example, functions such as open () write () creat () will return-1 in some cases, that is, call failure, at this time, you often need to

Work queue [Overview] A work queue is a form of pushing and executing jobs. A work queue can push jobs to a kernel thread for execution. It has all the advantages of the process context and allows rescheduling and sleep.   [Work queue implementation]

Tasklet [Overview] Tasklet is a special implementation of Soft Interrupt. Tasklet is usually the optimization mechanism of the lower half of the processing, which has a good balance between performance and ease of use. Compared with softirq, tasklet

Someone asked, How can I write a driver for so long? Indeed, it is not easy for everyone to go all the way, but now that we have reached today, we can only stick to it. Usb_stor_acquire_resources () is used to obtain resources by name. What is a

I thought this was the case in my life. I refused to look at the code again with an impetuous mind. However, two years later, I went to Las Vegas earlier this month and found that it was not a night package to find an American lady there for $ eight

For the case where use_sg is 0, let's look at the second row. offset is the parameter passed in by the function call. It is clear in the comment that it is used to mark the offset, each time you copy several bytes, it adds several bytes, and the

Use of git tool in Linux I believe that people who have worked on projects have a deep understanding of the importance of Software Version Management. If the program version is not properly managed, it may be a fatal blow to the entire project.

Module_param () Learning 1. module_param1. Why?In user mode, you can use main () to pass command line parameters, while compile a kernel module to pass command line parameters through module_param.2. The module_param macro is added to the Linux 2.6

In usb_stor_bulk_transport (), the first most important function called in this function is usb_stor_bulk_transfer_buf (). Still from drivers/USB/Stroage/transport. C: 391 int usb_stor_bulk_transfer_buf (struct us_data * us, unsigned int pipe, 392

Sometimes I am also troubled by this problem. I don't know whether I don't understand or whether the world is changing too fast. Even Linux introduces the concept of expiration. Set a time. If the time has reached, some things will happen. For

Summary LinuxCompression and decompression methods for various formats of compressed packages. However, I have not used some of the methods. I hope you can help me with them. I will modify them at any time. Thank you! Sorting: fish that can swimFrom:

3 i2c-dev 3.1 Overview Previously speaking about the I2C subsystem, I mentioned using i2c-dev.c files to implement our I2C Slave Device Driver in applications. However, it implements a virtual, temporary i2c_client, which is generated as the device

How to obtain system information through programs in Linux Recently, I was working on a project to dynamically obtain the hardware information of the device in the program. I have struggled for a long time. Today, I suddenly found that API functions

The first file_operations member is not an operation at all; it is a pointer to a module with this structure. This member is used to prevent the module from being detached when its operations are still in use. Almost all the time, it is

10. Platform 10.1 Overview L a real Linux Device and driver usually need to be mounted on a bus. This is naturally not a problem for devices that are attached to PCI, USB, IIC, SPI, etc, however, in an embedded system, an independent peripheral

Transplantation of some common libraries in ARM-LINUX 10:51:47 | category:Arm-Linux | label:| Large font size, medium/small subscription Some libraries are often reused in various projects. such as JPEG, FreeType, and iconv. each large project will