Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210430072138.6537-1-jbx6244@gmail.com>
In-Reply-To: <20210430072138.6537-1-jbx6244@gmail.com>
From:   Rob Herring <robh+dt@kernel.org>
Date:   Mon, 3 May 2021 17:40:48 -0500
Message-ID: <CAL_JsqKnD1t7oRDY5sTi3TjJ0vbFK0tQcVj1qCw_jiOfOQh=mA@mail.gmail.com>
Subject: Re: [RFC PATCH v1] dt-bindings: mmc: snps,dwcmshc-sdhci: fix rockchip,txclk-tapnum
To:     Johan Jonker <jbx6244@gmail.com>
Cc:     heiko@sntech.de, shawn.lin@rock-chips.com, ulf.hansson@linaro.org,
        Jisheng.Zhang@synaptics.com, linux-mmc@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Fri, Apr 30, 2021 at 2:21 AM Johan Jonker <jbx6244@gmail.com> wrote:
>
> A test with the command below gives this error:
> mmc@fe310000: rockchip,txclk-tapnum: missing size tag in [[8]]
>
> With this added to a dts file:
> rockchip,txclk-tapnum = <0x8>;
>
> A look at the driver shows that:
> DLL_TXCLK_TAPNUM_DEFAULT        0x8
>
> Adding the default value to the dts files is not needed.
> Every clock is divided into 32 taps equally and
> the max value is 31.
>
> Fix rockchip,txclk-tapnum property in snps,dwcmshc-sdhci.yaml by
> adding a minimum, maximum and default.
>
> In the driver the function of_property_read_u8() is used,
> but with dtbs_check the notifications only disappear in YAML
> by changing uint8 to uint32.

Did you check what value the driver sees when you put 8 in the dts. I
expect it will be 0 because you are reading the 1st byte in big
endian.

> The driver has no limit check for rockchip,txclk-tapnum.
>
> make ARCH=arm64 dtbs_check
>
> Signed-off-by: Johan Jonker <jbx6244@gmail.com>
> ---
>  Documentation/devicetree/bindings/mmc/snps,dwcmshc-sdhci.yaml | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/snps,dwcmshc-sdhci.yaml b/Documentation/devicetree/bindings/mmc/snps,dwcmshc-sdhci.yaml
> index e6c9a2f77..f43d8d829 100644
> --- a/Documentation/devicetree/bindings/mmc/snps,dwcmshc-sdhci.yaml
> +++ b/Documentation/devicetree/bindings/mmc/snps,dwcmshc-sdhci.yaml
> @@ -48,7 +48,10 @@ properties:
>
>    rockchip,txclk-tapnum:
>      description: Specify the number of delay for tx sampling.
> -    $ref: /schemas/types.yaml#/definitions/uint8
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    minimum: 0
> +    maximum: 31
> +    default: 8
>
>
>  required:
> --
> 2.11.0
>