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    SubjectRe: [PATCH v2 03/15] dmaengine: Add no_wakeup parameter to dmaengine_prep_dma_cyclic()
    Hi,

    On 09/14/2012 11:50 AM, Vinod Koul wrote:
    >> Well, the idea was that the driver would disable interrupts if there is no
    >> callback to call, since there would be nothing to do in the interrupt
    >> handler anyway. But I guess the flags approach should work fine as well.
    > Yes we _could_ do that, but this relies on dmaengine driver to have this
    > implicit understanding. Anyone using dmaengine library in ASoC may or
    > may not be aware of this, so i would consider it hackish.
    >
    > Using this flag explicitly makes everyone aware what the intended
    > behaviour is.

    I'm not sure about which flags should ASoC set for the two case we are going
    to have. I think it should be something like this:

    unsigned long flags = DMA_CTRL_ACK;

    if (!substream->runtime->no_period_wakeup)
    flags |= DMA_PREP_INTERRUPT;

    I'm not 100% sure of the role of DMA_CTRL_ACK in this case. Or should we only
    handle the DMA_PREP_INTERRUPT flag, like this:

    unsigned long flags = 0;

    if (!substream->runtime->no_period_wakeup)
    flags |= DMA_PREP_INTERRUPT;


    What do you think?

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