Re: [PATCH] mmc: Fix force card detect in sdhci

From: Adrian Hunter
Date: Mon Sep 04 2023 - 03:38:22 EST


+ Eugen Hristev

On 30/08/23 12:23, mathieu wrote:
> From: Mathieu Moneyron <mathieu.moneyron@xxxxxxxxx>
>
> On the ATMEL at91 when using the non-removable flag in device tree and not
> using the card-detect pin inside the device-tree pinctrl, the card detect
> pin is physically still used which can cause unknown behaviour when this
> pin is used for other purposes.
>
> From my interpretation this seems to be caused by a hardware design flaw
> and the real hardware is not working as intended by the documentation.
>
> Signed-off-by: Mathieu Moneyron <mathieu.moneyron@xxxxxxxxx>
> ---
> drivers/mmc/host/sdhci-of-at91.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c
> index 69fef88e7..4fd6bfbf6 100644
> --- a/drivers/mmc/host/sdhci-of-at91.c
> +++ b/drivers/mmc/host/sdhci-of-at91.c
> @@ -51,10 +51,15 @@ struct sdhci_at91_priv {
> static void sdhci_at91_set_force_card_detect(struct sdhci_host *host)
> {
> u8 mc1r;
> + u8 ctrl;
>
> mc1r = readb(host->ioaddr + SDMMC_MC1R);
> mc1r |= SDMMC_MC1R_FCD;
> writeb(mc1r, host->ioaddr + SDMMC_MC1R);
> +
> + ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
> + ctrl |= SDHCI_CTRL_CDTEST_INS | SDHCI_CTRL_CDTEST_EN;
> + writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);
> }
>
> static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock)