[PATCH] mmc: Fix force card detect in sdhci

Adrian Hunter adrian.hunter at intel.com
Mon Sep 4 00:38:11 PDT 2023


+ Eugen Hristev

On 30/08/23 12:23, mathieu wrote:
> From: Mathieu Moneyron <mathieu.moneyron at gmail.com>
> 
> 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 at gmail.com>
> ---
>  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)




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