As a next step to dma-engine based cppi4.1 driver implementation
this RFC has the overview of changes in the musb driver.
RFC on CPPI slave driver changes will follow next.
Overview of changes in the musb driver
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1)Add a dma-engine.c file in the drivers/usb/musb folder
2)This file will host the current musb dma APIs and translates them to
dmaengine APIs.
3)This will help to keep the changes in drivers/usb/musb/musb* files
minimal and also to retain compatibility other DMA (Mentor etc.)
drivers which are yet to be moved to drivers/dma
4)drivers/usb/musb/dma-engine.c, will wrap the dmaengine APIs to
make existing musb APIs compatible.
5)drivers/usb/musb/dma-engine.c file will implement the filter
functions and also implement .dma_controller_create (allocates
& provides "dma_controller" object) and .dma_controller_delete
6)CPPI4.1 DMA specific queue and buffer management will be internal
to slave CPPI DMA driver implementation.