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    SubjectRe: [PATCH 7/8] dmaengine/dw_dmac: Unmap all memory buffers after completion of slave transfers
    On Mon, Jan 16, 2012 at 12:44 PM, Viresh Kumar <> wrote:
    > On 1/16/2012 4:24 PM, Russell King - ARM Linux wrote:
    >> Note that DMA engine drivers are not responsible for unmapping the buffers
    >> when the transfer completes - that is the responsibility of the caller.
    >> The automatic buffer unmapping is required for the async_tx APIs and
    >> offload APIs.
    > In dw_dmac, it is only done for slave transfers. Is this Okay ??

    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

    Why do you want to do this?

    Linus Walleij

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      Last update: 2012-01-17 09:55    [W:0.019 / U:157.684 seconds]
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