mmc: fix division by zero in MMC core

The card is not always clocked and the clock frequency zero is perfectly
legal, thus this code in mmc_set_data_timeout() may cause a division by
zero. It will be triggered more often if you're using software clock
gating but can be triggered under other conditions too.

Reported-by: Pierre Tardy <tardyp@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Reviewed-by: Chris Ball <cjb@laptop.org>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Linus Walleij 2011-01-05 00:44:32 +01:00 committed by Chris Ball
parent 2bd6a93555
commit e9b86841b3

View file

@ -299,6 +299,7 @@ void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
unsigned int timeout_us, limit_us; unsigned int timeout_us, limit_us;
timeout_us = data->timeout_ns / 1000; timeout_us = data->timeout_ns / 1000;
if (mmc_host_clk_rate(card->host))
timeout_us += data->timeout_clks * 1000 / timeout_us += data->timeout_clks * 1000 /
(mmc_host_clk_rate(card->host) / 1000); (mmc_host_clk_rate(card->host) / 1000);