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References: <20221207051909.32126-1-wenchao.chen@unisoc.com>
In-Reply-To: <20221207051909.32126-1-wenchao.chen@unisoc.com>
From:   Ulf Hansson <ulf.hansson@linaro.org>
Date:   Fri, 9 Dec 2022 10:33:49 +0100
Message-ID: <CAPDyKFr=GYHAtt6EitO=o_Z+w0+6b_TWmLWLT_55Qn=5kX7DyQ@mail.gmail.com>
Subject: Re: [PATCH] mmc: sdhci-sprd: Disable CLK_AUTO when the clock is less
 than 400K
To:     Wenchao Chen <wenchao.chen@unisoc.com>
Cc:     adrian.hunter@intel.com, orsonzhai@gmail.com,
        baolin.wang@linux.alibaba.com, zhang.lyra@gmail.com,
        linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
        zhenxiong.lai@unisoc.com, yuelin.tang@unisoc.com
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Precedence: bulk

On Wed, 7 Dec 2022 at 06:20, Wenchao Chen <wenchao.chen@unisoc.com> wrote:
>
> When the clock is less than 400K, some SD cards fail to initialize
> because CLK_AUTO is enabled.
>
> Fixes: fb8bd90f83c4 ("mmc: sdhci-sprd: Add Spreadtrum's initial host controller")
> Signed-off-by: Wenchao Chen <wenchao.chen@unisoc.com>

Applied for next, and by adding a stable tag, thanks!

Kind regards
Uffe

> ---
>  drivers/mmc/host/sdhci-sprd.c | 16 +++++++++-------
>  1 file changed, 9 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c
> index bec3f9e3cd3f..525f979e2a97 100644
> --- a/drivers/mmc/host/sdhci-sprd.c
> +++ b/drivers/mmc/host/sdhci-sprd.c
> @@ -228,13 +228,15 @@ static inline void _sdhci_sprd_set_clock(struct sdhci_host *host,
>         div = ((div & 0x300) >> 2) | ((div & 0xFF) << 8);
>         sdhci_enable_clk(host, div);
>
> -       /* enable auto gate sdhc_enable_auto_gate */
> -       val = sdhci_readl(host, SDHCI_SPRD_REG_32_BUSY_POSI);
> -       mask = SDHCI_SPRD_BIT_OUTR_CLK_AUTO_EN |
> -              SDHCI_SPRD_BIT_INNR_CLK_AUTO_EN;
> -       if (mask != (val & mask)) {
> -               val |= mask;
> -               sdhci_writel(host, val, SDHCI_SPRD_REG_32_BUSY_POSI);
> +       /* Enable CLK_AUTO when the clock is greater than 400K. */
> +       if (clk > 400000) {
> +               val = sdhci_readl(host, SDHCI_SPRD_REG_32_BUSY_POSI);
> +               mask = SDHCI_SPRD_BIT_OUTR_CLK_AUTO_EN |
> +                       SDHCI_SPRD_BIT_INNR_CLK_AUTO_EN;
> +               if (mask != (val & mask)) {
> +                       val |= mask;
> +                       sdhci_writel(host, val, SDHCI_SPRD_REG_32_BUSY_POSI);
> +               }
>         }
>  }
>
> --
> 2.17.1
>