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

From: Mark Brown
Date: Tue Sep 07 2010 - 11:38:15 EST


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>
---
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;
--
1.7.1

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