Windows KMDF USB device Driver : Read API hangs ReadCompletion Routine Never gets called

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Windows

driver

Hello ALL,

I am writing a KMDF USB driver based upon the USBSAMP sample.

Firmware Scenarior:
*. Firmware will write to end point at its own wish. For example user has press mute button on device if so then my UI application should get/read those message and display on GUI.

*. My application is having one single thread for read and write one below other.

Problem
*. Writing is works fine from application to device.
*. But my Read API got hangs since i dont have data to read from the device.(As Device will write at its own wish (based upon some processing)

Code
1 .Call of ReadAPI readfile , triggers a break point in my registerd read Callback event that is

WDF_IO_QUEUE_CONFIG_INIT_DEFAULT_QUEUE(&ioQueueConfig,
WdfIoQueueDispatchParallel);
ioQueueConfig.EvtIoRead = UsbSamp_EvtIoRead;

2. Read Event calls the WdfRequestSend with correct I/0 target but its corrosponds register completion routin is never getting called as this time there is nothing to read...

3. How do i solve this problem ...
4. IS KMDF Continous Reader a solution to this. If yes please guide me on the same.