| Message ID | 1461171092-30631-1-git-send-email-aisheng.dong@nxp.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 20 April 2016 at 18:51, Dong Aisheng <aisheng.dong@nxp.com> wrote: > Currently MMC core will keep going if HS200/HS timing switch failed > with -EBADMSG error by the assumption that the old timing is still valid. > > However, for mmc_select_hs200 case, the signal voltage may have already > been switched. If the timing switch failed, we should fall back to > the old voltage in case the card is continue run with legacy timing. > > If fall back signal voltage failed, we explicitly report an EIO error > to force retry during the next power cycle. > > Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> > --- > drivers/mmc/core/mmc.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index b8aa12c..f6683a9 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -1245,9 +1245,11 @@ static int mmc_select_hs200(struct mmc_card *card) > struct mmc_host *host = card->host; > bool send_status = true; > unsigned int old_timing; > + unsigned int old_signal_voltage; Nitpick; you can merge this change into the line above. > int err = -EINVAL; > u8 val; > > + old_signal_voltage = host->ios.signal_voltage; > if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_2V) > err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120); > > @@ -1256,7 +1258,7 @@ static int mmc_select_hs200(struct mmc_card *card) > > /* If fails try again during next card power cycle */ > if (err) > - goto err; > + return err; > > mmc_select_driver_type(card); > > @@ -1290,9 +1292,14 @@ static int mmc_select_hs200(struct mmc_card *card) > } > } > err: > - if (err) > + if (err) { > + /* fall back to the old signal voltage, if fails report error */ > + if (__mmc_set_signal_voltage(host, old_signal_voltage)) > + err = -EIO; > + > pr_err("%s: %s failed, error %d\n", mmc_hostname(card->host), > __func__, err); > + } > return err; > } > > -- > 1.9.1 > Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 28 April 2016 at 11:26, Ulf Hansson <ulf.hansson@linaro.org> wrote: > On 20 April 2016 at 18:51, Dong Aisheng <aisheng.dong@nxp.com> wrote: >> Currently MMC core will keep going if HS200/HS timing switch failed >> with -EBADMSG error by the assumption that the old timing is still valid. >> >> However, for mmc_select_hs200 case, the signal voltage may have already >> been switched. If the timing switch failed, we should fall back to >> the old voltage in case the card is continue run with legacy timing. >> >> If fall back signal voltage failed, we explicitly report an EIO error >> to force retry during the next power cycle. >> >> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> >> --- >> drivers/mmc/core/mmc.c | 11 +++++++++-- >> 1 file changed, 9 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c >> index b8aa12c..f6683a9 100644 >> --- a/drivers/mmc/core/mmc.c >> +++ b/drivers/mmc/core/mmc.c >> @@ -1245,9 +1245,11 @@ static int mmc_select_hs200(struct mmc_card *card) >> struct mmc_host *host = card->host; >> bool send_status = true; >> unsigned int old_timing; >> + unsigned int old_signal_voltage; > > Nitpick; you can merge this change into the line above. > Applied for next with a minor change dealing with the nitpick above, thanks! Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index b8aa12c..f6683a9 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -1245,9 +1245,11 @@ static int mmc_select_hs200(struct mmc_card *card) struct mmc_host *host = card->host; bool send_status = true; unsigned int old_timing; + unsigned int old_signal_voltage; int err = -EINVAL; u8 val; + old_signal_voltage = host->ios.signal_voltage; if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_2V) err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120); @@ -1256,7 +1258,7 @@ static int mmc_select_hs200(struct mmc_card *card) /* If fails try again during next card power cycle */ if (err) - goto err; + return err; mmc_select_driver_type(card); @@ -1290,9 +1292,14 @@ static int mmc_select_hs200(struct mmc_card *card) } } err: - if (err) + if (err) { + /* fall back to the old signal voltage, if fails report error */ + if (__mmc_set_signal_voltage(host, old_signal_voltage)) + err = -EIO; + pr_err("%s: %s failed, error %d\n", mmc_hostname(card->host), __func__, err); + } return err; }
Currently MMC core will keep going if HS200/HS timing switch failed with -EBADMSG error by the assumption that the old timing is still valid. However, for mmc_select_hs200 case, the signal voltage may have already been switched. If the timing switch failed, we should fall back to the old voltage in case the card is continue run with legacy timing. If fall back signal voltage failed, we explicitly report an EIO error to force retry during the next power cycle. Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> --- drivers/mmc/core/mmc.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)