Author Topic: Add an endpoint to a composite device  (Read 6517 times)

felix34

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Add an endpoint to a composite device
« on: June 14, 2012, 05:45:26 am »
Hello everybody,

I hope someone can help me.
I'm using an audio device ( build on a dev board "dsp kit edzp 5535  from Texas instrument" with the entire source code included).
the device use the standart audio drivers on windows and linux and it works fine..Among the interfaces of this device there is a HID interface interrupt endpoint IN and
i can get  via hid report the state of two switch present on the board ( for volume mute..).I can read the hid report from linux with a hdiapi based application  without disturbing the windows drivers.
But i would add at the HID interface an interrupt endpoint OUT to toogle the state of a led on the board...before begin the work i need to know i'm not facing an impossible issue.

My questions are:
1-if i add and OUT endpoint to the HID interface, will the device continue to work with the standart audio class drivers of windows?
(in the book of Jan, ii seems that audio class device can have  zero or one interrupt endpoint ( second edition page 183).

2-is it possible to modify the HID report of a device  audio class driver to add some features without troubling the windows  audio class  drivers?
( extending the size of the HID report ...)

3-In case  of the point 2 is not possible,if i don't modify and don't add a interrupt OUT endpoint to the HID interface...can i add a second HID interface to the device
without troubling the standart class audio drivers? ( to have a specific hid report to meet my needs ).

Thank you for your help.

Felix   


     

Jan Axelson

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Re: Add an endpoint to a composite device
« Reply #1 on: June 14, 2012, 09:37:57 am »
Add a new HID interface for the LED.

Jan