Subject: Re: [PATCH 2/3] powerpc/esdhc: add property to disable the CMD23

From: Scott Wood <[email-masked]>
Date: Tue, 11 Sep 2012 13:28:17 -0500

On 09/11/2012 03:04 AM, Anton Vorontsov wrote:
> On Tue, Sep 11, 2012 at 12:54:29AM -0700, Anton Vorontsov wrote:
>> On Tue, Sep 11, 2012 at 03:12:44PM +0800, [email-masked] wrote:
>>> From: Jerry Huang <[email-masked]>
>>>
>>> Below SOCs don't support the cmd23 command for MMC card,
>>> therefore, disable it in device tree:
>>> P1020, P1021, P1022, P1024, P1025 and P4080
>>>
>>> Signed-off-by: Jerry Huang <[email-masked]>
>>
>> Acked-by: Anton Vorontsov <[email-masked]>
> 
> Btw, although the patch is trivial, I guess you still want to let know
> PowerPC folks about it. Adding Cc and copying the patch:
> 
> - - - -
> From: Jerry Huang <[email-masked]>
> 
> Below SOCs don't support the cmd23 command for MMC card,
> therefore, disable it in device tree:
> P1020, P1021, P1022, P1024, P1025 and P4080
> 
> Signed-off-by: Jerry Huang <[email-masked]>
> CC: Anton Vorontsov <[email-masked]>
> ---
>  arch/powerpc/boot/dts/fsl/p1020si-post.dtsi |    1 +
>  arch/powerpc/boot/dts/fsl/p1021si-post.dtsi |    1 +
>  arch/powerpc/boot/dts/fsl/p1022si-post.dtsi |    1 +
>  arch/powerpc/boot/dts/fsl/p4080si-post.dtsi |    1 +
>  4 files changed, 4 insertions(+)
> 
> diff --git a/arch/powerpc/boot/dts/fsl/p1020si-post.dtsi b/arch/powerpc/boot/dts/fsl/p1020si-post.dtsi
> index 68cc5e7..793a30b 100644
> --- a/arch/powerpc/boot/dts/fsl/p1020si-post.dtsi
> +++ b/arch/powerpc/boot/dts/fsl/p1020si-post.dtsi
> @@ -154,6 +154,7 @@
>  	sdhc@2e000 {
>  		compatible = "fsl,p1020-esdhc", "fsl,esdhc";
>  		sdhci,auto-cmd12;
> +		sdhci,no-cmd23;
>  	};
>  /include/ "pq3-sec3.3-0.dtsi"
>  
> diff --git a/arch/powerpc/boot/dts/fsl/p1021si-post.dtsi b/arch/powerpc/boot/dts/fsl/p1021si-post.dtsi
> index adb82fd..2b7fd2a 100644
> --- a/arch/powerpc/boot/dts/fsl/p1021si-post.dtsi
> +++ b/arch/powerpc/boot/dts/fsl/p1021si-post.dtsi
> @@ -149,6 +149,7 @@
>  /include/ "pq3-esdhc-0.dtsi"
>  	sdhc@2e000 {
>  		sdhci,auto-cmd12;
> +		sdhci,no-cmd23;
>  	};
>  
>  /include/ "pq3-sec3.3-0.dtsi"
> diff --git a/arch/powerpc/boot/dts/fsl/p1022si-post.dtsi b/arch/powerpc/boot/dts/fsl/p1022si-post.dtsi
> index 06216b8..2334a52 100644
> --- a/arch/powerpc/boot/dts/fsl/p1022si-post.dtsi
> +++ b/arch/powerpc/boot/dts/fsl/p1022si-post.dtsi
> @@ -215,6 +215,7 @@
>  	sdhc@2e000 {
>  		compatible = "fsl,p1022-esdhc", "fsl,esdhc";
>  		sdhci,auto-cmd12;
> +		sdhci,no-cmd23;
>  	};
>  
>  /include/ "pq3-sec3.3-0.dtsi"
> diff --git a/arch/powerpc/boot/dts/fsl/p4080si-post.dtsi b/arch/powerpc/boot/dts/fsl/p4080si-post.dtsi
> index 8d35d2c..5b39952 100644
> --- a/arch/powerpc/boot/dts/fsl/p4080si-post.dtsi
> +++ b/arch/powerpc/boot/dts/fsl/p4080si-post.dtsi
> @@ -337,6 +337,7 @@
>  	sdhc@114000 {
>  		voltage-ranges = <3300 3300>;
>  		sdhci,auto-cmd12;
> +		sdhci,no-cmd23;
>  	};
>  
>  /include/ "qoriq-i2c-0.dtsi"
> 

This won't help people with old device trees (forked for a custom board,
tied to an old U-Boot, etc).  The driver should infer this from the
compatible string or version registers (ideally block-specific version
registers, but if these are absent or inconclusive, SVR can be used).

-Scott