| Message ID | 1342184235-6912-1-git-send-email-girish.shivananjappa@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jul 13, 2012 at 6:27 PM, Girish K S <girish.shivananjappa@linaro.org> wrote: > The call to the mmc_power_up during the mmc_start_host breaks the card > detection in design-ware host controller. This patch removes the call to > mmc_power_up function during host start. > Please explain why. Which commit introduced it ? > This fix works fine with sdhci (sdhci compatilble host controller) > and dw_mmc (design-ware host controller). and has no side effect due to > this removal. > How can you be sure ? What about other hosts ? -- 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 17 July 2012 16:22, S, Venkatraman <svenkatr@ti.com> wrote: > On Fri, Jul 13, 2012 at 6:27 PM, Girish K S > <girish.shivananjappa@linaro.org> wrote: >> The call to the mmc_power_up during the mmc_start_host breaks the card >> detection in design-ware host controller. This patch removes the call to >> mmc_power_up function during host start. >> > Please explain why. Which commit introduced it ? dw_mmc card detection is broken by this commit fa5501890d8974301042e0202d342a6cbe8609f4 > >> This fix works fine with sdhci (sdhci compatilble host controller) >> and dw_mmc (design-ware host controller). and has no side effect due to >> this removal. >> > How can you be sure ? What about other hosts ? I have tested on the available host controllers. It would be helpful if others test it and let me know whether this change of mine causes any problem. -- 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
Hi Girish, On 13 July 2012 14:57, Girish K S <girish.shivananjappa@linaro.org> wrote: > The call to the mmc_power_up during the mmc_start_host breaks the card > detection in design-ware host controller. This patch removes the call to > mmc_power_up function during host start. > > This fix works fine with sdhci (sdhci compatilble host controller) > and dw_mmc (design-ware host controller). and has no side effect due to > this removal. > > Tested on : origen-board and smdk-5250 board. > > Signed-off-by: Girish K S <girish.shivananjappa@linaro.org> > Cc: Ulf Hansson <ulf.hansson@linaro.org> > --- > drivers/mmc/core/core.c | 1 - > 1 files changed, 0 insertions(+), 1 deletions(-) > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > index 9503cab..503aefc 100644 > --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -2108,7 +2108,6 @@ void mmc_start_host(struct mmc_host *host) > { > host->f_init = max(freqs[0], host->f_min); > host->rescan_disable = 0; > - mmc_power_up(host); This will introduce a bug (race condition) for host drivers using the regulator API (from regulator_init_complete) and for eMMC. So please do not remove this. > mmc_detect_change(host, 0); > } > > -- > 1.7.4.1 > I suggest you find out more details about why this breaks the card detection mechanism for your stated boards. Kind regards Ulf Hansson -- 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/core.c b/drivers/mmc/core/core.c index 9503cab..503aefc 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -2108,7 +2108,6 @@ void mmc_start_host(struct mmc_host *host) { host->f_init = max(freqs[0], host->f_min); host->rescan_disable = 0; - mmc_power_up(host); mmc_detect_change(host, 0); }
The call to the mmc_power_up during the mmc_start_host breaks the card detection in design-ware host controller. This patch removes the call to mmc_power_up function during host start. This fix works fine with sdhci (sdhci compatilble host controller) and dw_mmc (design-ware host controller). and has no side effect due to this removal. Tested on : origen-board and smdk-5250 board. Signed-off-by: Girish K S <girish.shivananjappa@linaro.org> Cc: Ulf Hansson <ulf.hansson@linaro.org> --- drivers/mmc/core/core.c | 1 - 1 files changed, 0 insertions(+), 1 deletions(-)