[RFC 2/5] dt: bcm2835-mmc bindings documentation

Stephen Warren swarren at wwwdotorg.org
Tue Oct 28 18:59:33 PDT 2014

On 10/28/2014 06:04 PM, Piotr Król wrote:

A patch description would be extremely useful.

We cannot have multiple DT bindings for the same HW; DT is supposed to
be an OS-/SW-agnostic description of the HW. Even if we did allow the
Linux kernel to contain multiple drivers for the same HW, that detail
would be something internal to the kernel, and not something that should
influence DT content in any way.

Instead, any missing information should be added to the existing
brcm,bcm2835-sdhci.txt as optional properties.

> diff --git a/Documentation/devicetree/bindings/mmc/brcm,bcm2835-mmc.txt b/Documentation/devicetree/bindings/mmc/brcm,bcm2835-mmc.txt

> +Example:
> +
> +mmc: mmc at 7e300000 {

> +		dmas = <&dma 5>,
> +		<&dma 5>;
> +		dma-names = "tx", "rx";

I would place dma-names as the first property in DT; it's the key to all
the others.

There's no need to wrap the dmas values onto two lines, but if you do,
please indent the subsequent lines so it's obvious it's a continuation
not a new property.

> +		status = "disabled";

Generally, the status property isn't included in examples.

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