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In my testing, both bytes_transferred or memcpy_count remain zero in all testing. However, I observed in_use is changes to 1 when the channel is requested. Inside the dmaengine: count += per_cpu_ptr(chan->local, i)->memcpy_count; I checked these variable to understand if my kernel driver is actually copying any data using DMA but it left me more confused. Can you please help in understanding its behavior? Thanks, Shivank