[PATCH v4 21/25] mmc: sdhci: fix data timeout (part 1)

Russell King
2016-01-29T09:45:39Z

The data timeout gives the minimum amount of time that should be
waited before timing out if no data is received from the card.
Simply dividing the nanosecond part by 1000 does not give this
required guarantee, since such a division rounds down. Use
DIV_ROUND_UP() to give the desired timeout.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
drivers/mmc/host/sdhci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 7fed845797a0..48bc0c6b74f7 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -633,7 +633,7 @@ static u8 sdhci_calc_timeout(struct sdhci_host *host, struct mmc_command *cmd)
if (!data)
target_timeout = cmd->busy_timeout * 1000;
else {
- target_timeout = data->timeout_ns / 1000;
+ target_timeout = DIV_ROUND_UP(data->timeout_ns, 1000);
if (host->clock)
target_timeout += data->timeout_clks / host->clock;
}
--
2.1.0