It is possible to turn off the card clock by setting the frequency to zero via debugfs e.g. echo 0 > /sys/kernel/debug/mmc0/clock However that produces an incorrect warning that is designed to warn if the frequency is below the minimum operating frequency. So correct the warning. Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> --- drivers/mmc/core/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index e2e1dd4..16aa7bd 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -995,7 +995,7 @@ void mmc_set_chip_select(struct mmc_host *host, int mode) */ static void __mmc_set_clock(struct mmc_host *host, unsigned int hz) { - WARN_ON(hz < host->f_min); + WARN_ON(hz && hz < host->f_min); if (hz > host->f_max) hz = host->f_max; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html