[PATCH 2/2] mmc: fsl_esdhc_imx: remove redundant cmd11 related code.

[ZHIZHIKIN Andrey]

> -----Original Message-----
> From: haibo.chen at nxp.com <haibo.chen at nxp.com>
> Sent: Wednesday, March 3, 2021 10:06 AM
> To: peng.fan at nxp.com; u-boot at lists.denx.de; sbabic at denx.de
> Cc: haibo.chen at nxp.com; uboot-imx at nxp.com; tharvey at gateworks.com;
> ZHIZHIKIN Andrey <andrey.zhizhikin at leica-geosystems.com>;
> festevam at gmail.com; ye.li at nxp.com
> Subject: [PATCH 2/2] mmc: fsl_esdhc_imx: remove redundant cmd11 related
> code.
> 
> From: Haibo Chen <haibo.chen at nxp.com>
> 
> Common code already handle the voltage switch sequence based on spec, so
> remove the redundant voltage switch code.
> 
> Signed-off-by: Haibo Chen <haibo.chen at nxp.com>
> ---
>  drivers/mmc/fsl_esdhc_imx.c | 10 +---------
>  1 file changed, 1 insertion(+), 9 deletions(-)
> 
> diff --git a/drivers/mmc/fsl_esdhc_imx.c b/drivers/mmc/fsl_esdhc_imx.c index
> af36558b3c..a199cf3df6 100644
> --- a/drivers/mmc/fsl_esdhc_imx.c
> +++ b/drivers/mmc/fsl_esdhc_imx.c
> @@ -515,15 +515,6 @@ static int esdhc_send_cmd_common(struct
> fsl_esdhc_priv *priv, struct mmc *mmc,
>                 goto out;
>         }
> 
> -       /* Switch voltage to 1.8V if CMD11 succeeded */
> -       if (cmd->cmdidx == SD_CMD_SWITCH_UHS18V) {
> -               esdhc_setbits32(&regs->vendorspec, ESDHC_VENDORSPEC_VSELECT);
> -
> -               printf("Run CMD11 1.8V switch\n");
> -               /* Sleep for 5 ms - max time for card to switch to 1.8V */
> -               udelay(5000);
> -       }
> -
>         /* Workaround for ESDHC errata ENGcm03648 */
>         if (!data && (cmd->resp_type & MMC_RSP_BUSY)) {
>                 int timeout = 50000;
> @@ -839,6 +830,7 @@ static int esdhc_set_voltage(struct mmc *mmc)
>                 }
>  #endif
>                 esdhc_setbits32(&regs->vendorspec, ESDHC_VENDORSPEC_VSELECT);
> +               mdelay(5);

Why is this delay introduced here? It is not clear from the commit message whether and why it is required here.

If this is kept from the removed block - maybe it is better to move the corresponding comment here as well.

>                 if (esdhc_read32(&regs->vendorspec) & ESDHC_VENDORSPEC_VSELECT)
>                         return 0;
> 
> --
> 2.17.1

-- andrey