Re: [PATCH 1/2] mmc: sdhci: Check card status after reset

From: Adrian Hunter
Date: Mon Sep 23 2019 - 08:33:19 EST


On 4/09/19 7:46 PM, Raul E Rangel wrote:
> In sdhci_do_reset we call the reset callback which is typically
> sdhci_reset. sdhci_reset can wait for up to 100ms waiting for the
> controller to reset. If SDHCI_RESET_ALL was passed as the flag, the
> controller will clear the IRQ mask. If during that 100ms the card is
> removed there is no notification to the MMC system that the card was
> removed. So from the drivers point of view the card is always present.
>
> By making sdhci_reinit compare the present state it can schedule a
> rescan if the card was removed while a reset was in progress.
>
> Signed-off-by: Raul E Rangel <rrangel@xxxxxxxxxxxx>

Should have Acked this ages ago, sorry :-(

Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>

> ---
> Sorry this took me so long to send out. I tested out the patch set on
> 5.3-rc5 with multiple devices.
>
> This patch was proposed here by Adrian: https://patchwork.kernel.org/patch/10925469/#22691177
>
> drivers/mmc/host/sdhci.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index a5dc5aae973e..b0045880ee3d 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -337,8 +337,19 @@ static void sdhci_init(struct sdhci_host *host, int soft)
>
> static void sdhci_reinit(struct sdhci_host *host)
> {
> + u32 cd = host->ier & (SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT);
> +
> sdhci_init(host, 0);
> sdhci_enable_card_detection(host);
> +
> + /*
> + * A change to the card detect bits indicates a change in present state,
> + * refer sdhci_set_card_detection(). A card detect interrupt might have
> + * been missed while the host controller was being reset, so trigger a
> + * rescan to check.
> + */
> + if (cd != (host->ier & (SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT)))
> + mmc_detect_change(host->mmc, msecs_to_jiffies(200));
> }
>
> static void __sdhci_led_activate(struct sdhci_host *host)
>