Re: [PATCH v2] mmc:sdhci: handle busy-end interrupt during command

[Ulf Hansson]

On 30 August 2014 05:40, Chanho Min <chanho.min@xxxxxxx> wrote:
> It is fully legal for a controller to start handling busy-end interrupt
> before it has signaled that the command has completed. So make sure
> we do things in the proper order, Or it results that command interrupt
> is ignored so it can cause unexpected operations. This is founded at some
> toshiba emmc with the bellow warning.
>
> "mmc0: Got command interrupt 0x00000001 even though
> no command operation was in progress."
>
> This issue has been also reported by Youssef TRIKI:
> It is not specific to Toshiba devices, and happens with eMMC devices
> as well as SD card which support Auto-CMD12 rather than CMD23.
>
> Also, similar patch is submitted by:
> Gwendal Grignou <gwendal@xxxxxxxxxxxx>
>
> Changes since v1:
>  Fixed conflict with the next of git.linaro.org/people/ulf.hansson/mmc.git
>  and Tested if issue is fixed again.
>
> Signed-off-by: Hankyung Yu <hankyung.yu@xxxxxxx>
> Signed-off-by: Chanho Min <chanho.min@xxxxxxx>
> Tested-by: Youssef TRIKI <youssef.triki@xxxxxx>

Thanks! Applied for next.

Kind regards
Uffe

> ---
>  drivers/mmc/host/sdhci.c  |   17 +++++++++++++++--
>  include/linux/mmc/sdhci.h |    1 +
>  2 files changed, 16 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index f6a683b..8428148 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -1016,6 +1016,7 @@ void sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd)
>         mod_timer(&host->timer, timeout);
>
>         host->cmd = cmd;
> +       host->busy_handle = 0;
>
>         sdhci_prepare_data(host, cmd);
>
> @@ -2261,8 +2262,12 @@ static void sdhci_cmd_irq(struct sdhci_host *host, u32 intmask)
>                 if (host->cmd->data)
>                         DBG("Cannot wait for busy signal when also "
>                                 "doing a data transfer");
> -               else if (!(host->quirks & SDHCI_QUIRK_NO_BUSY_IRQ))
> +               else if (!(host->quirks & SDHCI_QUIRK_NO_BUSY_IRQ)
> +                               && !host->busy_handle) {
> +                       /* Mark that command complete before busy is ended */
> +                       host->busy_handle = 1;
>                         return;
> +               }
>
>                 /* The controller does not support the end-of-busy IRQ,
>                  * fall through and take the SDHCI_INT_RESPONSE */
> @@ -2330,7 +2335,15 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
>                                 return;
>                         }
>                         if (intmask & SDHCI_INT_DATA_END) {
> -                               sdhci_finish_command(host);
> +                               /*
> +                                * Some cards handle busy-end interrupt
> +                                * before the command completed, so make
> +                                * sure we do things in the proper order.
> +                                */
> +                               if (host->busy_handle)
> +                                       sdhci_finish_command(host);
> +                               else
> +                                       host->busy_handle = 1;
>                                 return;
>                         }
>                 }
> diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
> index 09ebe57..0aa85ca 100644
> --- a/include/linux/mmc/sdhci.h
> +++ b/include/linux/mmc/sdhci.h
> @@ -146,6 +146,7 @@ struct sdhci_host {
>         struct mmc_command *cmd;        /* Current command */
>         struct mmc_data *data;  /* Current data request */
>         unsigned int data_early:1;      /* Data finished before cmd */
> +       unsigned int busy_handle:1;     /* Handling the order of Busy-end */
>
>         struct sg_mapping_iter sg_miter;        /* SG state for PIO */
>         unsigned int blocks;    /* remaining PIO blocks */
> --
> 1.7.9.5
>
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