Hi Addy, On Sat, Feb 14, 2015 at 11:47 AM, Addy Ke <addy.ke@xxxxxxxxxxxxxx> wrote: > As show in mmc_power_up(), in MMC_POWER_UP state, the voltage isn't > stable and we may get 'data busy' which can't be cleaned by resetting > all blocks. So we should not send command to update clock in this state. > > Signed-off-by: Addy Ke <addy.ke@xxxxxxxxxxxxxx> > --- > drivers/mmc/host/dw_mmc.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c > index 4d2e3c2..3472f9b 100644 > --- a/drivers/mmc/host/dw_mmc.c > +++ b/drivers/mmc/host/dw_mmc.c > @@ -1102,7 +1102,8 @@ static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > drv_data->set_ios(slot->host, ios); > > /* Slot specific timing and width adjustment */ > - dw_mci_setup_bus(slot, false); > + if (ios->power_mode != MMC_POWER_UP) > + dw_mci_setup_bus(slot, false); > This looks a HACK to me. If stabilizing host voltage regulator is the problem, can you try out below patch, and see if this resolve your issue? =========== [PATCH] mmc: dw_mmc: Wait for host voltage regulator to be stable Signed-off-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx> --- drivers/mmc/host/dw_mmc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 4d2e3c2..dc10fbb 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -1202,6 +1202,9 @@ static int dw_mci_switch_voltage(struct mmc_host *mmc, struct mmc_ios *ios) } mci_writel(host, UHS_REG, uhs); + /* wait for 5ms so that host voltage regulator is stable */ + usleep_range(5000, 5500); + return 0; } =============== > if (slot->host->state == STATE_WAITING_CMD11_DONE && ios->clock != 0) > slot->host->state = STATE_IDLE; > -- > 1.8.3.2 > > -- Regards, Alim -- 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
