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    SubjectRe: i810_audio
    Nathan Bryant wrote:

    > 1) Is the LVI interrupt supposed to arrive when the chip *starts*
    > playing the last buffer?
    > 2) Does SiS actually do it this way?
    > If your theory on why the registers are spinning is correct, and if we
    > receive the LVI interrupt with too much latency, your code will still
    > deadlock, Doug. (The LVI interrupt handler calls update_ptr first
    > thing, which calls get_dma_address.) Furthermore, if this turns out to
    > be the case, the LVI IRQ handler uses dmabuf->count to determine
    > whether to call stop_dac, and needs to call update_ptr to update
    > dmabuf->count... so an explicit stop_dac might be needed elsewhere.
    > Even if the LVI interrupt comes at the beginning of the buffer, those
    > 2048 bytes will play in 10.67 ms. Can we really guarantee that kind of
    > latency?

    Add to this, if SiS isn't sending DCH, and LVI arrives at the beginning
    of the last buffer, count is still > 0, so we don't call stop_dac. And
    we're right back where we started.

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