On 10/11/16 18:47, Michael Walle wrote:
> Since commit 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy
> cards in __mmc_switch()") the ESDHC driver is broken:
> mmc0: Card stuck in programming state! __mmc_switch
> mmc0: error -110 whilst initialising MMC card
>
> Since this commit __mmc_switch() uses ->card_busy(), which is
> sdhci_card_busy() for the esdhc driver. sdhci_card_busy() uses the
> PRESENT_STATE register, specifically the DAT0 signal level bit. But the
> ESDHC uses a non-conformant PRESENT_STATE register, thus a read fixup is
> required to make the driver work again.
>
> Signed-off-by: Michael Walle <mich...@walle.cc>
Could add a Fixes tag here.
> ---
> drivers/mmc/host/sdhci-of-esdhc.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-esdhc.c
> b/drivers/mmc/host/sdhci-of-esdhc.c
> index fb71c86..243fee9 100644
> --- a/drivers/mmc/host/sdhci-of-esdhc.c
> +++ b/drivers/mmc/host/sdhci-of-esdhc.c
> @@ -66,6 +66,18 @@ static u32 esdhc_readl_fixup(struct sdhci_host *host,
> return ret;
> }
> }
> + /*
> + * The DAT[3:0] line signal levels and the CMD line signal level is
> + * not compatible with standard SDHC reegister. Move the corresponding
reegister -> register
> + * bits around.
> + */
> + if (spec_reg == SDHCI_PRESENT_STATE) {
> + ret = value & 0xf8000000;
> + ret |= (value >> 4) & SDHCI_DATA_LVL_MASK;
> + ret |= (value << 1) & 0x01000000;
> + return ret;
SDHCI also uses other bits in SDHCI_PRESENT_STATE like SDHCI_CMD_INHIBIT and
SDHCI_DATA_INHIBIT etc, but this looks like all those bits will be zero. Is
that right?
> + }
> +
> ret = value;
> return ret;
> }
>
