Hi, Alim Sorry for late reply. On 2015/2/16 07:28, Alim Akhtar wrote: > 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? I have test by: cd /sys/bus/platform/drivers/dwmmc_rockchip for i in $(seq 1 10000); do echo "========================" $i echo ff0c0000.dwmmc > unbind sleep .5 echo ff0c0000.dwmmc > bind sleep 2 done There is no error. I think this patch can resolve my issue, thank you. Do you send this patch upstream, or can I put it in my patch list? > > =========== > [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 >> >> > > > -- 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
