Re: [PATCH 1/3] mmc: host: omap_hsmmc: Fix DTO and DCRC handling

[Andreas Fenkart]

Hi Vignesh,

2015-06-16 12:37 GMT+02:00 Vignesh R <vigneshr@xxxxxx>:
> From: Kishon Vijay Abraham I <kishon@xxxxxx>
>
> DTO/DCRC errors were not being informed to the mmc core since
> commit ae4bf788ee9b ("mmc: omap_hsmmc: consolidate error report handling of
> HSMMC IRQ"). This commit made sure 'end_trans' is never set on DTO/DCRC
> errors. This is because after this commit 'host->data' is checked after
> it has been cleared to NULL by omap_hsmmc_dma_cleanup().
>
> Because 'end_trans' is never set, omap_hsmmc_xfer_done() is never invoked
> making core layer not to be aware of DTO/DCRC errors. Because of this
> any command invoked after DTO/DCRC error leads to a hang.
>
> Fix this by checking for 'host->data' before it is actually cleared.

This really fixes the problem, thanks for the analysis
TESTED-BY

>
> Fixes: ae4bf788ee9b ("mmc: omap_hsmmc: consolidate error report handling of
> HSMMC IRQ")
>
> CC: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> Signed-off-by: Vignesh R <vigneshr@xxxxxx>
> ---
>  drivers/mmc/host/omap_hsmmc.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index 9df2b6801f76..d0abdffb0d7c 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -1062,6 +1062,10 @@ static void omap_hsmmc_do_irq(struct omap_hsmmc_host *host, int status)
>
>                 if (status & (CTO_EN | CCRC_EN))
>                         end_cmd = 1;
> +               if (host->data || host->response_busy) {
> +                       end_trans = !end_cmd;
> +                       host->response_busy = 0;
> +               }
>                 if (status & (CTO_EN | DTO_EN))
>                         hsmmc_command_incomplete(host, -ETIMEDOUT, end_cmd);
>                 else if (status & (CCRC_EN | DCRC_EN))
> @@ -1081,10 +1085,6 @@ static void omap_hsmmc_do_irq(struct omap_hsmmc_host *host, int status)
>                         }
>                         dev_dbg(mmc_dev(host->mmc), "AC12 err: 0x%x\n", ac12);
>                 }
> -               if (host->data || host->response_busy) {
> -                       end_trans = !end_cmd;
> -                       host->response_busy = 0;
> -               }
>         }
>
>         OMAP_HSMMC_WRITE(host->base, STAT, status);
> --
> 2.4.1
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
Please read the FAQ at  http://www.tux.org/lkml/