[PATCH 4.5 197/238] mmc: sdhci: fix data timeout (part 1)

From: Greg Kroah-Hartman
Date: Sun Apr 10 2016 - 14:54:09 EST


4.5-stable review patch. If anyone has any objections, please let me know.

------------------

From: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>

commit fafcfda9e78cae8796d1799f14e6457790797555 upstream.

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@xxxxxxxxxxxxxxxx>
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Tested-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mmc/host/sdhci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -635,7 +635,7 @@ static u8 sdhci_calc_timeout(struct sdhc
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;
}