Re: [PATCH 2/2] spi/spi_s3c64xx: Increase dead reckoning time in wait_for_xfer()

[Jassi Brar]

On Wed, Sep 8, 2010 at 12:37 AM, Mark Brown
<broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
> ---
> Âdrivers/spi/spi_s3c64xx.c | Â Â2 +-
> Â1 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,
>
> Â Â Â Â/* millisecs to xfer 'len' bytes @ 'cur_speed' */
> Â Â Â Âms = xfer->len * 8 * 1000 / sdd->cur_speed;
> - Â Â Â ms += 5; /* some tolerance */
> + Â Â Â ms += 10; /* some tolerance */
>
> Â Â Â Âif (dma_mode) {
> Â Â Â Â Â Â Â Âval = msecs_to_jiffies(ms) + 10;

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