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    SubjectRe: [PATCHv5] DMAEngine: Define interleaved transfer request api
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    On Fri, 2011-10-14 at 23:38 +0800, Barry Song wrote:
    > Vinod, actually it is not decided by codec. it is only related with
    > the hardware of pcm, i2s or AC'97 controllers in SoC. i did remember
    > some people once licensed a TDM tranfer enginee from synopsys and IC
    > guys bound one TDM slot, which has a seperate dma channel, to one
    > audio channel then organize several TDM slots into a AC97 controller.
    Not sure if I follow you.
    For i2s and pcm you send left/right channel and then right/left channel.
    Data is sent interleaved. DMA also treats it same way.
    I don't know about AC97 so wont comment about it
    >
    > i am on holiday now and i can't give you more information until next
    > week.
    >
    > Still i saw most other chips binding multi-channels of an I2S/PCM/AC97
    > audio controller in a dma channel, then it doesn't need interleaved
    > dma api as its dma address will increase continuously. dma will
    > transfer left+right together but not one left and one right.
    Right :)

    --
    ~Vinod



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