[PATCH 3/3] mmc: host: omap_hsmmc: avoid possible overflow of timeout value

From: Ravikumar Kattekola
Date: Mon Jan 30 2017 - 05:18:44 EST


Fixes: a45c6cb81647 ("[ARM] 5369/1: omap mmc: Add new omap
hsmmc controller for 2430 and 34xx, v3")

when using really large timeout (up to 4*60*1000 ms for bkops)
there is a possibility of data overflow using
unsigned int so use 64 bit unsigned long long.

Signed-off-by: Ravikumar Kattekola <rk@xxxxxx>
Signed-off-by: Sekhar Nori <nsekhar@xxxxxx>
---
drivers/mmc/host/omap_hsmmc.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 51ca3d7..a58bd65 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -1469,10 +1469,11 @@ static int omap_hsmmc_setup_dma_transfer(struct omap_hsmmc_host *host,
}

static void set_data_timeout(struct omap_hsmmc_host *host,
- unsigned int timeout_ns,
+ unsigned long long timeout_ns,
unsigned int timeout_clks)
{
- unsigned int timeout, cycle_ns;
+ unsigned long long timeout = timeout_ns;
+ unsigned int cycle_ns;
uint32_t reg, clkd, dto = 0;

reg = OMAP_HSMMC_READ(host->base, SYSCTL);
@@ -1481,7 +1482,7 @@ static void set_data_timeout(struct omap_hsmmc_host *host,
clkd = 1;

cycle_ns = 1000000000 / (host->clk_rate / clkd);
- timeout = timeout_ns / cycle_ns;
+ do_div(timeout, cycle_ns);
timeout += timeout_clks;
if (timeout) {
while ((timeout & 0x80000000) == 0) {
@@ -1527,7 +1528,7 @@ static void omap_hsmmc_start_dma_transfer(struct omap_hsmmc_host *host)
omap_hsmmc_prepare_data(struct omap_hsmmc_host *host, struct mmc_request *req)
{
int ret;
- unsigned int timeout;
+ unsigned long long timeout;

host->data = req->data;

--
1.9.1