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    SubjectRe: [PATCH 7/8] dmaengine/dw_dmac: Unmap all memory buffers after completion of slave transfers
    On 1/17/2012 2:22 PM, Linus Walleij wrote:
    > Basically the driver using the dmaengine shall map/unmap buffers
    > used for slave transfers, not the driver.
    >
    > I usually map them before setting up a transfer and unmaps them
    > when egtting the callback from the DMA engine that the transfer is
    > complete.
    >

    You implemented similar stuff in amba-pl08x :) .

    if (!plchan->slave)
    pl08x_unmap_buffers(txd);

    > Why do you want to do this?

    This is because people can pass in flags which are
    DMA_COMPL_SKIP_SRC_UNMAP, etc.

    If they are not passed, then DMA driver must do it for them.

    Sorry if i am understanding the DMA logic incorrectly.

    --
    viresh


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