diff options
| -rw-r--r-- | drivers/mmc/host/atmel-mci.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 9819dc09ce0..34080f590f6 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -482,7 +482,14 @@ err: static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host, unsigned int ns) { - return (ns * (host->bus_hz / 1000000) + 999) / 1000; + /* + * It is easier here to use us instead of ns for the timeout, + * it prevents from overflows during calculation. + */ + unsigned int us = DIV_ROUND_UP(ns, 1000); + + /* Maximum clock frequency is host->bus_hz/2 */ + return us * (DIV_ROUND_UP(host->bus_hz, 2000000)); } static void atmci_set_timeout(struct atmel_mci *host, |