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Message-ID: <9c93dd3e-f80d-7421-05b8-9f692d33d2f2@linux.alibaba.com>
Date:   Wed, 30 Nov 2022 18:42:20 +0800
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Subject: Re: [PATCH] mmc: sdhci-sprd: Fix no reset data and command after
 voltage switch
To:     Wenchao Chen <wenchao.chen@unisoc.com>, adrian.hunter@intel.com,
        ulf.hansson@linaro.org, orsonzhai@gmail.com, zhang.lyra@gmail.com
Cc:     linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
        zhenxiong.lai@unisoc.com, yuelin.tang@unisoc.com,
        gengcixi@gmail.com
References: <20221130080224.12831-1-wenchao.chen@unisoc.com>
From:   Baolin Wang <baolin.wang@linux.alibaba.com>
In-Reply-To: <20221130080224.12831-1-wenchao.chen@unisoc.com>
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On 11/30/2022 4:02 PM, Wenchao Chen wrote:
> After switching the voltage, no reset data and command will cause
> CMD2 timeout.
> 
> Fixes: 29ca763fc26f ("mmc: sdhci-sprd: Add pin control support for voltage switch")
> Signed-off-by: Wenchao Chen <wenchao.chen@unisoc.com>
> ---
>   drivers/mmc/host/sdhci-sprd.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c
> index b92a408f138d..464508be8ec8 100644
> --- a/drivers/mmc/host/sdhci-sprd.c
> +++ b/drivers/mmc/host/sdhci-sprd.c
> @@ -470,7 +470,7 @@ static int sdhci_sprd_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
>   	}
>   
>   	if (IS_ERR(sprd_host->pinctrl))
> -		return 0;
> +		goto reset;
>   
>   	switch (ios->signal_voltage) {
>   	case MMC_SIGNAL_VOLTAGE_180:
> @@ -496,6 +496,7 @@ static int sdhci_sprd_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
>   		break;
>   	}
>   
> +reset:
>   	/* Wait for 300 ~ 500 us for pin state stable */
>   	usleep_range(300, 500);

If no pin state switching, still need stable time? Otherwise looks good 
to me.

>   	sdhci_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);