| Message ID | 1424370173-63422-1-git-send-email-mreimer@sdgsystems.com |
|---|---|
| State | Accepted |
| Delegated to: | Pantelis Antoniou |
| Headers | show |
Hi Matt, > On Feb 19, 2015, at 20:22 , Matt Reimer <mreimer@sdgsystems.com> wrote: > > Fix bus width switching from 8-bit mode down to 4-bit or 1-bit modes on > Samsung SoCs using SDHCI_QUIRK_USE_WIDE8. These SoCs report controller > version 2.0 yet they support 8-bit bus widths. If 8-bit mode was > previously enabled and then an operation like "mmc dev" caused a switch > back down to 4-bit or 1-bit mode, WIDE8 was left set, causing failures. > > This problem was manifested by "mmc dev" timing out. > > Signed-off-by: Matt Reimer <mreimer@sdgsystems.com> > --- > drivers/mmc/sdhci.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c > index de88e19..82d7984 100644 > --- a/drivers/mmc/sdhci.c > +++ b/drivers/mmc/sdhci.c > @@ -374,7 +374,8 @@ static void sdhci_set_ios(struct mmc *mmc) > (host->quirks & SDHCI_QUIRK_USE_WIDE8)) > ctrl |= SDHCI_CTRL_8BITBUS; > } else { > - if (SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) > + if ((SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) || > + (host->quirks & SDHCI_QUIRK_USE_WIDE8)) > ctrl &= ~SDHCI_CTRL_8BITBUS; > if (mmc->bus_width == 4) > ctrl |= SDHCI_CTRL_4BITBUS; > -- > 1.7.9.5 > Good catch, applied, thanks. — Pantelis
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index de88e19..82d7984 100644 --- a/drivers/mmc/sdhci.c +++ b/drivers/mmc/sdhci.c @@ -374,7 +374,8 @@ static void sdhci_set_ios(struct mmc *mmc) (host->quirks & SDHCI_QUIRK_USE_WIDE8)) ctrl |= SDHCI_CTRL_8BITBUS; } else { - if (SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) + if ((SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) || + (host->quirks & SDHCI_QUIRK_USE_WIDE8)) ctrl &= ~SDHCI_CTRL_8BITBUS; if (mmc->bus_width == 4) ctrl |= SDHCI_CTRL_4BITBUS;
Fix bus width switching from 8-bit mode down to 4-bit or 1-bit modes on Samsung SoCs using SDHCI_QUIRK_USE_WIDE8. These SoCs report controller version 2.0 yet they support 8-bit bus widths. If 8-bit mode was previously enabled and then an operation like "mmc dev" caused a switch back down to 4-bit or 1-bit mode, WIDE8 was left set, causing failures. This problem was manifested by "mmc dev" timing out. Signed-off-by: Matt Reimer <mreimer@sdgsystems.com> --- drivers/mmc/sdhci.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)