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    SubjectRe: [PATCH v9 4/6] media: uvcvideo: Allow hw clock updates with buffers not full
    On (23/03/15 14:30), Ricardo Ribalda wrote:
    > With UVC 1.5 we get as little as one clock sample per frame. Which means
    > that it takes 32 frames to move from the software timestamp to the
    > hardware timestamp method.
    >
    > This results in abrupt changes in the timestamping after 32 frames (~1
    > second), resulting in noticeable artifacts when used for encoding.
    >
    > With this patch we modify the update algorithm to work with whatever
    > amount of values are available.
    >
    > Tested-by: HungNien Chen <hn.chen@sunplusit.com>
    > Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>

    Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>

    > + * Have at least 1/4 of a second of timestamps before we
    > + * try to do any calculation. Otherwise we do not have enough
    > + * precision. This value was determined by running Android CTS
    > + * on different devices.
    > + * Dev_sof runs at 1KHz, and we have a fixed point precision of
    > + * 16 bits.
    > + */
    > + if ((y2 - y1) < ( (1000 / 4) << 16))

    A minor nit: extra space `( (` :)

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