device mapper

PCI device creation process This part is divided into two parts for learning. One is to refer to the previous articles, analyze the source code of ld1_and sculld, and the other is to refer to ldd3 to learn PCI. Part 1Ldd_bus declares the ldd_bus_type of a bus_type structure: Struct bus_type ldd_bus_type = { . Name = "LDD ", . Match = ldd_match, . Uevent = ldd_uevent, }; The code for adding ldd_bus_type to and detaching from the kernel is as follows:

As there are too many notes in Chapter 10, I will post the previous notes first. 1. functions used to open various devices Device Function used to open a device File Createfile (pszname is the path name or UNC path name) Directory Createfile (pszname is the path name or UNC path name ). if you specify the file_flag_backup_semantics flag when calling createfile, Windows al

First, we know that the driver is part of the kernel, so what role does the driver play in the kernel?The role of the device driver in the kernel: they are separate "black boxes" that enable a particular hardware to respond to a well-defined internal programming interface that completely hides the work details of the device. (Plainly, the driver does not have any implementation details that are invisible to

2.1Network Driver StructureThe architecture 1 of the Linux Network Driver is shown in.It can be divided into four layers:(1) Protocol Interface Layer (2) network device interface layer (3) Device Driver Function Layer (4) network device and media layer. Network Driver Focus: completes the device driver Function Layer I

How to use the device tree of linux drivers and how to use the device tree of linux drivers The Device Tree describes the hardware from the software perspective, and DTS is the Device Tree source file. DTC is responsible for converting DTS to DTB, and DTB is the binary form of DTS for machine use. The

This article was reproduced from: http://blog.csdn.net/ymangu666/article/details/39292651Primary, secondary device numberThe application can access the actual device by reading and writing to the device files in the/dev directory.1) Each device file corresponds to two device

Linux character device-simple character device model Linux character Devices I. Use the character Device Driver 1. Compile/install the driverIn Linux, drivers generally use the program structure of the kernel module for encoding. Therefore, the essence of compiling/installing a driver is to compile/install a kernel module. 2. Character

first, how to operate the equipment The operation of the device in Linux is done by means of a file, including open, read, and write. For device files, it is generally called a device node, The node has a property that is the device number (the primary device number, the se

Reference:Http://elinux.org/Device_Tree_Usagehttp://blog.csdn.net/sgmenghuo/article/details/45071615 Basic Data Format The device tree is a simple tree structure that contains nodes and attributes. Properties are described by the form of key-value pairs, a node can contain multiple attributes or child nodes, and a simple. DTS format device tree is shown below. /dts-v1/; /{ Node1 { A-string-prop

Smart Device Security: China's online smart device Security Situation Report in 2017, and the situation report in 2017 Smart Device Security: China's online smart device Security Situation Report in 2017. In recent years, security incidents of online smart devices have occurred from time to time, and CNCERT has continu

./////////////////////////////////////////////////////////////////////////////////////////////////////////////// ////When your device is idle, it will first darken the screen, then turn off the mask (that is, the black screen, you have to press the power key and so on to re-charge it), will eventually turn off the phone's CPU, the purpose is to prevent the device's battery quickly exhausted, but many times, your program may request some unusual behavi

In the article on the Linux System file type classification we mentioned the block device and the character device file, then what is the block device character device file? What are the fundamental differences between them?The device files are divided into blocks (block)

Device numberThe device number consists of the main device number and the secondary device number. Linux, all devices are files, all devices can find the corresponding files in the/ dev directory. These files, in addition to their names, have different device numbers for eac

From: http://www.cnblogs.com/zhuyp1015/archive/2012/05/22/2514008.html bird1015 blog When writing a Linux kernel driver, if you do not dynamically generate a device number, you need to manually allocate the device number. It is possible that the device number you allocate will be the same as the existing device number

A Linux device model can be better understood through various stages of a device's life cycle in the kernel. I will analyze the source code of ldquo and sculld to understand the integration of each link in the Linux device model. The integration of the (PCI Bus) in ldd3 serves as a reference, because embedded Linux uses less PCI bus. First, you must familiarize yourself with the source code of ldquo and scu

The character device or block device definition belongs to the device access layer of the operating system, which is not necessarily related to the characteristics of the actual physical device. The driver is under the device access layer, so you only need to provide the dri