cyclic sdma - determine either number of bytes written or current ARM destination Adress

[ericgrunt]

I'm on the Linux platform and using sdma via dmaegine and the sdma-imx driver

to copy data from uart to Memory (DEV_TO_MEM).

I need to access data written by cyclic dma before an interrupt is issued,

so I do not know the transfer length.

Accessing mode.count of struct sdma_buffer_descriptor does not give an answer,

since it just holds the buffers full size.

How is the information, which adress the dma write next to accessible outside the sdma driver?

Or is there an alternate way to find out how many bytes have been written during a single transfer?

[igorpadykov]

Hi Eric

I am afraid sdma driver does not provide info about current

memory address which it is accessing, so seems there is no way

to know how many bytes were written.

Best regards

igor

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