Increase timeout by 30 ms for some wiggle room and set the minimum value
to 100 ms. This ensures a non-zero value for short transfers which
may take less than 1 ms. The timeout value does not affect
performance because it is used with a completion.
Similar formula is used in other drivers e.g. sun4i, sun6i.
Reviewed-by: Krzysztof Kozlowski <k...@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelm...@samsung.com>
---
drivers/spi/spi-s3c64xx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 89c162efe355..ea5a22dec53d 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -473,7 +473,8 @@ static int s3c64xx_wait_for_dma(struct
s3c64xx_spi_driver_data *sdd,
/* millisecs to xfer 'len' bytes @ 'cur_speed' */
ms = xfer->len * 8 * 1000 / sdd->cur_speed;
- ms += 10; /* some tolerance */
+ ms += 30; /* some tolerance */
+ ms = max(ms, 100); /* minimum timeout */
val = msecs_to_jiffies(ms) + 10;
val = wait_for_completion_timeout(&sdd->xfer_completion, val);
--
2.26.2
