On 13 August 2012 11:19, Dmitry Rozhkov <dmitry.rozhkov@xxxxxxxxxxxxxxx> wrote: > According to p6.4.1.1 of the Physical Layer Simplified Specification > Ver3.01 the "host needs to keep power line level less than 0.5V and > more than 1ms before power ramp up". This patch adds an explicit delay > of 10ms just before power rump up. > > Without this patch some microSD cards (e.g. Kingston 8G Class 10) can't be > used as bootable media on some TI OMAP chips at least. > See https://bugs.nemomobile.org/show_bug.cgi?id=92 for details. > > Signed-off-by: Dmitry Rozhkov <dmitry.rozhkov@xxxxxxxxxxxxxxx> > --- > drivers/mmc/core/core.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > index 0b6141d..22b0eb2 100644 > --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -1163,6 +1163,13 @@ static void mmc_power_up(struct mmc_host *host) > > mmc_host_clk_hold(host); > > + /* > + * According to p6.4.1.1 of the Physical Layer Simplified Specification > + * Ver3.01 the "host needs to keep power line level less than 0.5V and > + * more than 1ms before power ramp up". > + */ > + mmc_delay(10); can you instead just try giving this delay in mmc_start_host as a parameter to mmc_detect_change. > + > /* If ocr is set, we use it */ > if (host->ocr) > bit = ffs(host->ocr) - 1; > -- > 1.7.9.5 > > -- > 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 -- 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
