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I am writing USB device emulator using Microsoft Usb Device Emulation framework.
So far I have implemented support for interrupt and bulk transfers, but isochronous transfers just do not work.
Driver sets up dynamic endpoints (UdecxUsbDeviceInitSetEndpointsType is called with UdecxEndpointTypeDynamic). So when virtual USB device is plugged (UdecxUsbDevicePlugIn), UDE framework calls callback for endpoint creation. There I create and associate queue with endpoint:
Here is a part of the code:
queueConfig.EvtIoInternalDeviceControl = OnTestIoInternalControl;
queueConfig.EvtIoCanceledOnQueue = OnTestCancelled;
queueConfig.EvtIoDefault = OnTestDefault;
queueConfig.EvtIoDeviceControl = OnTestIoControl;
queueConfig.EvtIoRead = OnTestRead;
queueConfig.EvtIoResume = OnTestResume;
queueConfig.EvtIoStop = OnTestStop;
queueConfig.EvtIoWrite = OnTestWrite;
WdfIoQueueCreate(hubDevice, &queueConfig, &queueAttributes, &queue);
UdecxUsbEndpointCreate(&endpointInit, &endpointAttributes, &udecxEndpoint);
Note: I have just extracted part of the code, to make this post as short as possible
For bulk and interrupt endpoints it works fine, but for isochronous endpoint no "Test" callbacks are called. From log I can see that UDE has created endpoint and queue. USBVIEW shows opened pipe for isochronous endpoint, but when I try to play some music (tested virtual USB is audio device) it just does not trigger any callbacks that I could use to transfer data.
Does anybody know is isochronous transfers supported at all by Microsoft UDE?
If so, is there any additional setup required to make this work?
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