motorola device drivers

transaction.The following is a method of using the struct with the C99 syntax, and the struct member that does not show the declaration is initialized to null by GCCstatic const struct File_operations Globalmem_fops = {. Owner = This_module,. Llseek = Globalmem_llseek,. Read = Globalmem_read,. write = Globalmem_write,. Unlocked_ioctl = globalmem_ioctl,/* in the kernel version of 2.6.x, in the file operation structure,Will have the IOCTL field, use Unlocked_ioctl in the higher version */. open =

Recently read a lot of kernel programming and drive development tutorials, also refer to some of the Development Board examples. The conclusion is not as high as you can imagine. Developing a driver requires a certain understanding of the kernel, not a thorough interpretation. The drivers referred to below are for specific devices and are made to work in dynamic loading of modules. The driver framework is layered, some

reader doesn't necessarily believe:Generic_make_request () is ultimately handled by calling the REQUEST_QUEUE.MAKE_REQUEST_FN function to complete the request described by bio.By the end of the story, we can now explain why we've listed the inexplicable data structure.For block device drivers, it is the REQUEST_QUEUE.MAKE_REQUEST_FN function that handles all requests on this block device.In other words, as

!Released on: February 1, February 09, 2006Level: elementaryAccess status: 3751 viewsSuggestion: 0 (add comments) 1. Get the kernel versionWhen the device driver needs to support different kernel versions at the same time, in the compilation phase, the kernel module needs to know the version of the currently used kernel source code to use the corresponding kernel API. In the 2.4 and 2.6 kernels, the source code header file linux/version. h is defined

Part I: The MMAP system call directly maps the device memory to the address space of the user process.Part II: Direct access to memory pages of user space across borders. Some related drivers require this capability (how user-space memory maps to the kernel method get_user_pages)Part III: Direct Memory access (DMA) I/O operations enable peripherals to have direct access to the system's memory capacity.Memor

Http://21cnbao.blog.51cto.com/109393/336263 1.1 Device Driver core layer and examples in the object-oriented programming, you can define a base class for a similar thing, specific things can inherit the functions in this base class. If the implementation of a function of the inherited object is the same as that of the base class, it can directly inherit the functions of the base class. On the contrary, it can be overloaded. This object-oriented design

Introduction plan for linux Device Drivers-general Linux technology-Linux programming and kernel information. For details, see the following section. Ldd2, that is, linux device driver 2nd. This book helps you understand the implementation of most hardware work through the Linux OpenSource OS. It is suitable for C programmer which is not very clear about the unde

the PCI system bus, both of which use physical addresses DIY Assignment The Get_free_pages function can allocate up to a few m bytes of memory, but for a larger number of requests, even requests that are much less than 128KB will typically fail because the system memory is full of memory fragmentation When the kernel cannot return the requested amount of memory or needs more than 128KB of memory, in addition to returning-enomem, another method is to allocate

[Blog.csdn.net/lanmanck] Once upon a while, we found a job as a driver engineer, with a low monthly salary. The Code of people we have never touched cannot be understood at all. Today is good. If we do not want to pursue differentiation, we can allow the system to communicate with USB devices without drivers. Linux will not talk about it. libusb is very useful. Now we will talk about windows. Winusb is a kind of middleware similar to libusb and USB

Preface Linux is a variant of the UNIX operating system, and the principle and idea of writing a driver in Linux is similar to that of other Unix systems, but it is very different for drivers in DOS or window environments. Design the driver in the Linux environment, the thought is concise, the operation is convenient, the function is also very formidable, but the support function is few, can only depend on the function in the kernel, some commonly us

Iot framework ServerSuperIO tutorial-19. device drivers and OPC Client Support persistence of mysql, oracle, sqlite, and sqlserver. V3.6.4 released, sqlite persistent 19. The device driver and OPC Client Support persistence of mysql, oracle, sqlite, and sqlserver. 19.1 Overview ServerSuperIO supports writing data collected by

Original URL: http://www.cnblogs.com/geneil/archive/2011/12/04/2275372.htmlIn addition to the ability to read and write devices, most drivers also require the ability to control hardware.First, in user space, using the IOCTL system call to control the device , the prototype is as follows:int ioctl (int fd,unsigned long cmd,...);/*FD: File descriptorCMD: Control command...: Optional parameter: Insert *ARGP,

1. Overview ... 22. Serversuperio.core Cross-platform development environment ... 23. Serversuperio.core features ... 24. Serversuperio.core and Serversuperio difference ... 25. Embedded applications ... 26. PC Application ... 27. Cloud Service Application ... 28. Application and test instructions, take the Linux platform as an example ... 2 Overview Our data-receiving services for the Big Data Platform (cloud) platform are based on Serversuperio development because of the m

versa. L stream DMA ing In this ing mode, the device driver must pay attention to the high-speed cache consistency problem, which can be solved by using appropriate synchronous auxiliary functions, also known as "Asynchronous" There is no high-speed cache consistency problem when using dma in the 80x86 architecture, because the device driver itself "snoop" The accessed hardware high-speed cache. Therefore,

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); if (!dev->users) check_disk_change (Inode->i_bdev);//Check if the media in the drive changes dev->users++;//increase user Count Spin_unlock (dev->lock); return 0; }To turn off the device function:static int sbull_release (struct inode *inode, struct file *filp) { struct sbull_dev *dev = inode->i_bdev- >bd_disk->private_data; Spin_lock (dev->lock); dev->users--; if (!dev->users) { dev->timer.expir

The driver can be compiled in two ways. One is to statically compile the program into the kernel, and the other is to compile the program into a module for dynamic loading. Because uClinux does not support dynamic module loading, and embedded Linux cannot use insmod/rmmod as flexibly as Desktop Linux does, so here we will only introduce how to statically compile the device driver into the uClinux kernel.The following uses uClinux as an example to desc

holds the processor context snapshot before the processor enters the interrupt code The interrupt processing routine should return a value that indicates whether an interrupt was actually handled, and if the processing routine finds that its device does need to be processed, it should return irq_handled, otherwise the return value should be Irq_none Enable and disable interrupts sometimes

blocking and non-blocking IO in Linux device drivers:Blocking and non-blocking in 1.Linux device drivers Summary: http://m.blog.csdn.net/blog/dongteen/17264501Blocking and non-blocking io:http://m.blog.csdn.net/blog/dongteen/17264501 in 2.Linux device driversBlocking and non-blocking I/O in 3.Linux

difference between the two can be seen if the application's call returns immediately!Drivers often need to provide the ability to make system calls, such as read (), write (), if the device's resources are not available, and the user wants to access the device in a blocking manner, the driver should be in the device-driven xxx_read (), Xxx_write (), and so on Th