[PATCH 1/2] sdhci-of-arasan: Add device tree parameter fails-without-test-cd bit

Rob Herring robh at kernel.org
Fri Sep 2 07:45:06 PDT 2016


On Mon, Aug 29, 2016 at 06:20:56PM -0500, Zach Brown wrote:
> The sdhci controller on xilinx zynq devices will not function unless
> the CD bit is provided. http://www.xilinx.com/support/answers/61064.html
> In cases where it is impossible to provide the CD bit in hardware,
> setting the controller to test mode and then setting inserted to true
> will get the controller to function without the CD bit.
> 
> The device property "fails-without-test-cd" will let the arasan driver know
> the controller does not have the CD line wired and that the controller
> does not function without it.
> 
> Signed-off-by: Zach Brown <zach.brown at ni.com>
> ---
> v2:
>  * improved commit messages
>  * removed fake-cd device property
>  * removed fake-cd quirk
>  * use broken-cd device property
>  * documented new usage of broken-cd
> v3:
>  * removed new usage of broken-cd
>  * created fails-without-test-cd device property
>  * created arasan controller specific quirk
> 
> 
>  Documentation/devicetree/bindings/mmc/arasan,sdhci.txt | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> index 3404afa..ec0dc82 100644
> --- a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> +++ b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> @@ -21,6 +21,10 @@ Required Properties:
>    - interrupts: Interrupt specifier
>    - interrupt-parent: Phandle for the interrupt controller that services
>  		      interrupts for this device.
> +Optional Properties:
> +- fails-without-test-cd: when present, the controller doesn't work when the CD
> +  line is not connected properly, and the line is not connected properly. Test
> +  mode can be used to force the controller to function.

Prefix with either arasan or xlnx. Seems more likely Xilinx specific to 
me.

Rob



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