I am currently developing a driver for an HID device on a FreeBSD system. The idea is that the driver writes to the device's registers through the Control Endpoint. From then on the device acts according to the data fed.
Since I have just started out on drivers, I am following a guide book (I would name it here but I don't know if I can? ). This book tackles a USB ULPT (Printer) driver, explaining the basic driver for a USB device. However when I am trying to implement these concepts to the HID device, I am having trouble, more specifically when it comes to identifying and probing the device.
Since I haven't found much material online, I was wondering are there any guides/books or tutorials I can follow which tackle the development of an HID device driver on FreeBSD or at least Linux systems. A pointer (pun intended) to the right direction would be enough to get me going again.
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I am trying to make a Windows driver for a bluetooth gamepad, I know exactly what data the gamepad sends via bluetooth, but I have no clue where to start with this project, I have searched far and wide for more information about how to recieve data through bluetooth with WDK, but I have yet to a good source of documentation or a good example. Everything has to be coded in C, I have already setup the basic driver and tested it on the device, all i need now is functionality.
So my questions are:
How do you connect to the right bluetooth device
How do you send/recieve bluetooth data using WDK
How do you emulate a HID gamepad device after parsing the bluetooth data
Any links to documentation, examples or possibly books would be much appreciated.
I am post-newbie to Embedded Linux driver development, have developed Character, UART & simple USB drivers, and have worked with SBC (Raspberry Pi 2). My main learning resources are: Essential Linux Device Drivers, Embedded Linux System Design & Development, youtube tutorials and LDD3. Because of lack of real life driver experience, I have some questions that I would like to share:
Templates: are there some sort of driver templates for speeding up the coding process e.g. have the regularly used structures & functions for being modified & customized for the specific drivers.
What’s suitable minimum distribution:
What I am doing now is either building a kernel image using Buildroot then inserting the developed USB driver into it OR inserting the developed USB driver into a Ubuntu. And for proper testing I have to unload the default USB driver (usb_storage); otherwise can’t test my module. So, my question is regarding real-life development & how-to get minimum kernel that has no drivers, & how-to include my module into it (to be part of it) while building with Buildroot?
What Embedded Linux Driver Development community do you suggest for detailed Q&A?
i.e. In future if I want to ask about low level detail such as what is this x structure, or I am getting this error while using this y function .... is there a specialized community? because all I found are for Linux in general, for Kernel hacking, or don’t have experiences.
What is the missed link in the chain?
Developing applications for Microcontrollers relies on Datasheet, User Guide, Registers, C, etc. Developing Drivers for Embedded Linux relies on C, Linux API, Subsystems, etc. In most learning resources, I never found a relationship between both. So, are there really separated? OR there is a missed link between them??
e.g. for this I2C sensor http://www.robot-electronics.co.uk/htm/srf10tech.htm we have to manipulate it (send hexa to & receive values from its registers). If we imagine that we want to develop an I2C driver for it, then for sure we would need to do the same from within the driver, which is explained in Essential Linux Device Drivers (page#278). The main point behind it is that I2C core hides many complexes & simplifies driver development process.
However, I expect the case in real life is not for a sensor, instead it might be a Microcontroller or a complicated device. So, how would we manipulate the Registers & Peripherals of this Microcontroller? Also, I didn’t find tutorial for such a case!
I bought a usb otoscope from the internet and I want to create an application that uses it. When I plug it into the computer, it reads the device as a USB Camera, and I can use the very barebones software supplied to communicate with it. I'm very new to the idea of communicating with usb all together. I've tried to look at some sites like this: http://www.jespersaur.com/drupal/book/export/html/21, that tell me how to reverse engineer a device. I don't know if I'm going down the right path with this...
I've downloaded USB Snoopy and I can't seem to get it to sniff the packets correctly. I also have Crunchbang linux installed on a different computer but I don't know how to sniff it on that either (especially because the drivers are native to windows). All I want is some sort of API/Interfacing functions for me to call and use. How do I go about doing such a thing? I'm able to locate the device on the device manager in windows, and it tells me hardware ID's and such. I can supply any information if necessary. Thank you.
EDIT - Small description I found of the otoscope: http://microscopesimgv.blogspot.com/2012/08/oasis-ehev2-usbplus-20mp-handheld-usb.html
would this tool help you any?libusbx is a cross-platform user mode library that provides generic access to USB devices
CHEERS!
I am currently practising with USB programming on an AT91SAM9G20-Evaluation Kit. I learned much about USB devices and USB device port drivers while "playing" with the ATMEL provided USB device port projects (CDC-driver, ..).
But now I'd like to write a small driver to controll a wireless stick
which I plugged into one of the boards USB-A Host Ports.
I read a lot on Stack Overflow, the OpenHCI specification and even found some libraries on the net, but I am not sure if it's a good way to implement my own stack without any "good" knowledge in USB Host Port programming.
Is there a small and easy way to control the wireless-stick at the boards USB Host port? (like using the USART-Interfaces?).
I am also keen to hear hints on how to implement RTUSB or libUSB in to the AT91.
You can download AT91LIB version 1.9 from atmel from this page
The usb host libraries are under at91lib/usb/host. They're not the complete package you need though since they're just the OHCI driver -- you still need a USB driver and class drivers to implement what you want.
You could try an RTOS with USB Host support like rt-usb32
How should I approach implementing a USB device driver for Windows? How should I take into account different versions of windows e.g:
- Windows XP
- Windows Vista
- Windows 7
Is there open source solutions which could be used as a starting point? I'm a total newbie to windows driver development.
We have an embedded device with USB device port and we would like to have as low latency communication from the application level to the device as possible without sacrificing the data throughput. The actual data transferred is ADC/DAC data. Basically there is a lot of data which we need to transfer to a Windows machine as fast as possible.
We need more information about the device to point you in the right direction, but here are a few steps to get you started:
register with Microsoft Connect so you can download the Windows Driver Kit
register with osr-online as you'll find great articles, plenty of information, and a newsgroup dediciated just to Windows drivers -- this place is a goldmine
buy Developing Drivers with WDF, which will help you make sense of driver development on Windows and give you a good foundation to read articles from OSR and Microsoft
Hope that you can use UMDF (user-mode drivers) as you can use C++ and just write COM code. If you're doing anything with USB that requires kernel-space....you've got a lot of reading and learning to do for the next year!
To answer your question on versions, the Driver Kit has tools that will help you manage creating different drivers. If you write a good driver, it should run on all three OS with no problems, and the differences will just be in the config area (not the binary)
Basically, it depends on how complex your device is. What type of driver are you trying to write? File system? MP3 player? Camera? Modem?
If you end up having to write a kernel mode driver, let me know and I can point you to some good articles and what not.
I should also add that for around US $5,000, you can buy a license for WinDriver, a tool that takes all of the hard stuff out of driver development. You can use C++ or C# user-mode code to communicate with their driver that is custom generated for your device. This is the way to go if you have a tight deadline.
You can take a look at windows variant of libusb *here*. There are wrappers for many programming languages on official libusb site and on the web.
Start here: Windows Driver Kit Introduction
If you have some form of control over the device side, have it implement an interface for which Windows already provides drivers. E.g. the USB HID class (literally Human Input Device, but neither the Human nor the Input is mandatory) already has Windows drivers, and there is a reasonable Win32 API on top. You're not going to get data rates anywhere near 480 Mbps, though.