From e9b86841b372de01ae865080118e29159d8b7c39 Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Wed, 5 Jan 2011 00:44:32 +0100 Subject: [PATCH] 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 Signed-off-by: Linus Walleij Reviewed-by: Chris Ball Cc: Signed-off-by: Chris Ball --- drivers/mmc/core/core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 4b1d8fb..6625c05 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -299,8 +299,9 @@ void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card) unsigned int timeout_us, limit_us; timeout_us = data->timeout_ns / 1000; - timeout_us += data->timeout_clks * 1000 / - (mmc_host_clk_rate(card->host) / 1000); + if (mmc_host_clk_rate(card->host)) + timeout_us += data->timeout_clks * 1000 / + (mmc_host_clk_rate(card->host) / 1000); if (data->flags & MMC_DATA_WRITE) /* -- 2.7.4