acked-by: Philip Rakity <prak...@marvell.com>

On Mar 1, 2012, at 4:18 AM, Ulf Hansson wrote:

> Even if cards supports 1.8V I/O voltage those should anyway be
> initialized at 3.3V I/O according to (e)MMC, SD and SDIO specs.
> Some eMMC and embedded SDIO devices are able to be initialized
> at 1.8V as well, but it is better to be safe.
> 
> Do note that initialization in this context means that the card
> has been completely powered off, otherwise the card will remain
> at the last I/O voltage level that were negotitiated.
> 
> Due to the above being taken care of the suspend/resume issues
> for UHS-I SD-cards has been fixed.
> 
> Change-Id: Ia906f69d44b5be8374b0b536881190f67757b03e
> Signed-off-by: Ulf Hansson <ulf.hans...@stericsson.com>
> ---
> drivers/mmc/core/core.c |    3 +++
> drivers/mmc/core/mmc.c  |    3 +++
> drivers/mmc/core/sd.c   |    8 +++-----
> drivers/mmc/core/sdio.c |    9 +++++++++
> 4 files changed, 18 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index 0b317f0..faa0af1 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -2074,6 +2074,9 @@ static int mmc_rescan_try_freq(struct mmc_host *host, 
> unsigned freq)
>        */
>       mmc_hw_reset_for_init(host);
> 
> +     /* Initialization should be done at 3.3 V I/O voltage. */
> +     mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
> +
>       /*
>        * sdio_reset sends CMD52 to reset card.  Since we do not know
>        * if the card is being re-initialized, just send it.  CMD52
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index 6b13776..6defddd 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -830,6 +830,9 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
>       if (!mmc_host_is_spi(host))
>               mmc_set_bus_mode(host, MMC_BUSMODE_OPENDRAIN);
> 
> +     /* Initialization should be done at 3.3 V I/O voltage. */
> +     mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
> +
>       /*
>        * Since we're changing the OCR value, we seem to
>        * need to tell some cards to go back to the idle
> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> index 5017f93..c272c686 100644
> --- a/drivers/mmc/core/sd.c
> +++ b/drivers/mmc/core/sd.c
> @@ -911,6 +911,9 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 
> ocr,
>       BUG_ON(!host);
>       WARN_ON(!host->claimed);
> 
> +     /* The initialization should be done at 3.3 V I/O voltage. */
> +     mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
> +
>       err = mmc_sd_get_cid(host, ocr, cid, &rocr);
>       if (err)
>               return err;
> @@ -1156,11 +1159,6 @@ int mmc_attach_sd(struct mmc_host *host)
>       BUG_ON(!host);
>       WARN_ON(!host->claimed);
> 
> -     /* Make sure we are at 3.3V signalling voltage */
> -     err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, false);
> -     if (err)
> -             return err;
> -
>       /* Disable preset value enable if already set since last time */
>       if (host->ops->enable_preset_value) {
>               mmc_host_clk_hold(host);
> diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
> index 12cde6e..dac2e23 100644
> --- a/drivers/mmc/core/sdio.c
> +++ b/drivers/mmc/core/sdio.c
> @@ -585,6 +585,10 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 
> ocr,
>        * Inform the card of the voltage
>        */
>       if (!powered_resume) {
> +
> +             /* The initialization should be done at 3.3 V I/O voltage. */
> +             mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
> +
>               err = mmc_send_io_op_cond(host, host->ocr, &ocr);
>               if (err)
>                       goto err;
> @@ -996,6 +1000,11 @@ static int mmc_sdio_power_restore(struct mmc_host *host)
>        * With these steps taken, mmc_select_voltage() is also required to
>        * restore the correct voltage setting of the card.
>        */
> +
> +     if (!mmc_card_keep_power(host))
> +             /* The initialization should be done at 3.3 V I/O voltage. */
> +             mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
> +
>       sdio_reset(host);
>       mmc_go_idle(host);
>       mmc_send_if_cond(host, host->ocr_avail);
> -- 
> 1.7.7.2
> 
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