Messages in this thread Patch in this message | | | Date | Thu, 24 Feb 2011 19:18:01 +0800 | From | Chuanxiao Dong <> | Subject | [PATCH 1/1]mmc: fix division by zero when calculate mmc erase time |
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Since if clock gating feature is enabled, the clock frequency may be zero when host clock is gated. In such scenario, mmc_set_mmc_erase_timeout() may have a division by zero bug.
So this patch used mmc_host_clk_rate() to fix this.
Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com> --- drivers/mmc/core/core.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 34a7e8c..12d0eb8 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -1201,8 +1201,14 @@ static void mmc_set_mmc_erase_timeout(struct mmc_card *card, * less but not that much less, so fudge it by multiplying by 2. */ timeout_clks <<= 1; - timeout_us += (timeout_clks * 1000) / - (card->host->ios.clock / 1000); + + /* + * at this moment, host controller maybe clock gated, so make + * sure we can get a correct host clock freq. + */ + if (mmc_host_clk_rate(card->host)) + timeout_us += (timeout_clks * 1000) / + (mmc_host_clk_rate(card->host) / 1000); erase_timeout = timeout_us / 1000; -- 1.6.6.1
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