Re: [PATCH v3 05/11] mmc: sdhci: Disable HS200 mode if controller can't support 1.8v

From: Adrian Hunter
Date: Thu Mar 15 2018 - 06:59:34 EST


On 07/03/18 15:20, Kishon Vijay Abraham I wrote:
> Though MMC controller can indicate HS200 mode capability (by
> using "mmc-hs200-1_8v" dt property), if the IO lines in the board
> is connected to 3.3v supply, HS200 mode cannot be supported.
> Such boards have "no-1-8-v" property in their dts file. Disable HS200
> mode for boards which have "no-1-8-v" set.
>
> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
> drivers/mmc/host/sdhci.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 2ededa7f43df..aa8b5ca0d1b0 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -3672,6 +3672,7 @@ int sdhci_setup_host(struct sdhci_host *host)
> if (host->quirks2 & SDHCI_QUIRK2_NO_1_8_V) {
> host->caps1 &= ~(SDHCI_SUPPORT_SDR104 | SDHCI_SUPPORT_SDR50 |
> SDHCI_SUPPORT_DDR50);
> + mmc->caps2 &= ~MMC_CAP2_HS200;

Pedantically, shouldn't that be:

~(MMC_CAP2_HS200_1_8V_SDR | MMC_CAP2_HS400_1_8V)

We have MMC_CAP2_HSX00_1_2V so maybe we should add:

#define MMC_CAP2_HSX00_1_8V (MMC_CAP2_HS200_1_8V_SDR | MMC_CAP2_HS400_1_8V)

And then

mmc->caps2 &= ~MMC_CAP2_HSX00_1_8V;

> }
>
> /* Any UHS-I mode in caps implies SDR12 and SDR25 support. */
>