[PATCH] mmc:Remove the legacy mode clock setting operation

Peng Fan peng.fan at oss.nxp.com
Mon Jun 26 03:01:34 CEST 2023



On 6/21/2023 11:11 AM, xf_hqu at 163.com wrote:
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> 
> From: xiefei <xf_hqu at 163.com>
> 
> Due to the need to read the register value before
> switching to hs mode, the standard protocol does
> not explicitly specify that the setting before
> switching to hs mode is in legacy mode. Therefore,
> the code at this point may cause communication
> abnormalities between the host and card
> 
> Signed-off-by: xiefei <xf_hqu at 163.com>
> ---
>   drivers/mmc/mmc.c | 1 -
>   1 file changed, 1 deletion(-)
> 
> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
> index 1af6af82e6..915f446973 100644
> --- a/drivers/mmc/mmc.c
> +++ b/drivers/mmc/mmc.c
> @@ -2138,7 +2138,6 @@ static int mmc_select_mode_and_width(struct mmc *mmc, uint card_caps)
>                  mmc_set_card_speed(mmc, MMC_HS, true);
>          else
>   #endif
> -               mmc_set_clock(mmc, mmc->legacy_speed, MMC_CLK_ENABLE);

Has you meet any issues without removing this line? or this is just code 
inpsection?

BTW the upper "else" will met issue if you directly remove this line.

Regards,
Peng.


> 
>          for_each_mmc_mode_by_pref(card_caps, mwt) {
>                  for_each_supported_width(card_caps & mwt->widths,
> --
> 2.17.1
> 


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