I'm trying to write a linux kernel module for the LS2088ARDB (running linux kernel 4.1.35-rt41) and after that also for the LX2160ARDB (running Linux kernel 4.9.62) that executes a DMA transfer from main memory to a PCIe device.
Therefore I want to use the Slave-DMA API of the linux dmaengine (documented here : <linux kernel>/Documentation/dmaengine/client.txt).
According to this doc the first step is to allocate a dma channel with 'dma_request_channel' (in later kernel versions the appropriate function is callled 'dma_request_chan'), but this step fails using my kernel module.
Is it possible to use this API on these boards, at all? Do the linux BSPs for these two boards support a dma controller that I can use for my purpose?