Hi Kevin,
On 26 September 2012 13:38, Kevin Liu <keyuan.liu@xxxxxxxxx> wrote:
> From: Kevin Liu <kliu5@xxxxxxxxxxx>
>
> Mmc does NOT have special sequence requirements for 1.8v
> signal voltage setting compared to sd and sdio.
> Add a new 1.8v flag for mmc so as to use the same
> start_signal_voltage_switch interface.
This problem is protocol issue and should not be solved in the host
driver. We have more issues for signal_voltage switch as well.
Please have a look at Johan Rudholms patches:
[PATCH v2 1/2] mmc: core: Proper signal voltage switch
[PATCH v2 2/2] mmc: core: Power cycle card on voltage switch fail
>
> Signed-off-by: Kevin Liu <kliu5@xxxxxxxxxxx>
> ---
> drivers/mmc/core/mmc.c | 3 ++-
> include/linux/mmc/host.h | 1 +
> 2 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index 7509de1..3aa7f14 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -758,7 +758,8 @@ static int mmc_select_hs200(struct mmc_card *card)
>
> if (err && card->ext_csd.card_type & EXT_CSD_CARD_TYPE_SDR_1_8V &&
> host->caps2 & MMC_CAP2_HS200_1_8V_SDR)
> - err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180, 0);
> + err = mmc_set_signal_voltage(host,
> + MMC_SIGNAL_VOLTAGE_MMC_180, 0);
>
> /* If fails try again during next card power cycle */
> if (err)
> diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
> index 0ee92d2..d9ab286 100644
> --- a/include/linux/mmc/host.h
> +++ b/include/linux/mmc/host.h
> @@ -71,6 +71,7 @@ struct mmc_ios {
> #define MMC_SIGNAL_VOLTAGE_330 0
> #define MMC_SIGNAL_VOLTAGE_180 1
> #define MMC_SIGNAL_VOLTAGE_120 2
> +#define MMC_SIGNAL_VOLTAGE_MMC_180 3
>
> unsigned char drv_type; /* driver type (A, B, C, D) */
>
> --
> 1.7.0.4
>
Kind regards
Ulf Hansson
--
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
