@@ -680,8 +680,19 @@ static u8 sdhci_calc_timeout(struct sdhci_host *host, struct mmc_command *cmd)
target_timeout = cmd->busy_timeout * 1000;
else {
target_timeout = DIV_ROUND_UP(data->timeout_ns, 1000);
- if (host->clock)
- target_timeout += data->timeout_clks / host->clock;
+ if (host->clock && data->timeout_clks) {
+ unsigned long long val;
+
+ /*
+ * data->timeout_clks is in units of clock cycles.
+ * host->clock is in Hz. target_timeout is in us.
+ * Hence, us = 1000000 * cycles / Hz. Round up.
+ */
+ val = 1000000 * data->timeout_clks;
+ if (do_div(val, host->clock))
+ target_timeout++;
+ target_timeout += val;
+ }
}
/*
This is a note to let you know that I have just added a patch titled mmc: sdhci: fix data timeout (part 2) to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.8-ckt18. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ---8<------------------------------------------------------------ From 43b2ec2c77ba57a5dffcbd98f21b70f33d59264d Mon Sep 17 00:00:00 2001 From: Russell King <rmk+kernel@arm.linux.org.uk> Date: Tue, 26 Jan 2016 13:41:04 +0000 Subject: mmc: sdhci: fix data timeout (part 2) commit 7f05538af71c7d30b5fc821cbe9f318edc645961 upstream. The calculation for the timeout based on the number of card clocks is incorrect. The calculation assumed: timeout in microseconds = clock cycles / clock in Hz which is clearly a several orders of magnitude wrong. Fix this by multiplying the clock cycles by 1000000 prior to dividing by the Hz based clock. Also, as per part 1, ensure that the division rounds up. As this needs 64-bit math via do_div(), avoid it if the clock cycles is zero. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/mmc/host/sdhci.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) -- 2.7.4