mmc: sdhci: fix data timeout (part 1)

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>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org # v3.15+
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 6fe0e78..1d1b3c5 100644 (file)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -635,7 +635,7 @@ 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;
        }