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SubjectRe: [PATCH 2/2] spi/spi_s3c64xx: Increase dead reckoning time in wait_for_xfer()
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On Wed, Sep 8, 2010 at 12:37 AM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
> For small transfers at high speeds the expected transfer time can easily
> be well under 1ms, causing the delay in wait_for_xfer() to be only the
> dead reckoning fudge factor of 5ms currently included. Experiments on
> some of my systems shows that this is marginal for some transfers so
> double it to 10ms.
>
> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
> ---
>  drivers/spi/spi_s3c64xx.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/spi/spi_s3c64xx.c b/drivers/spi/spi_s3c64xx.c
> index 03b28e4..4abb441 100644
> --- a/drivers/spi/spi_s3c64xx.c
> +++ b/drivers/spi/spi_s3c64xx.c
> @@ -326,7 +326,7 @@ static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
>
>        /* millisecs to xfer 'len' bytes @ 'cur_speed' */
>        ms = xfer->len * 8 * 1000 / sdd->cur_speed;
> -       ms += 5; /* some tolerance */
> +       ms += 10; /* some tolerance */
>
>        if (dma_mode) {
>                val = msecs_to_jiffies(ms) + 10;

Acked-by: Jassi Brar <jassi.brar@samsung.com>
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