[PATCH 3/7] mmc: dw_mmc: add device tree support

[Olof Johansson]

Hi,

On Tue, May 1, 2012 at 10:07 PM, Thomas Abraham
<thomas.abraham at linaro.org> wrote:
> Add device tree based discovery support.
>
> Signed-off-by: Thomas Abraham <thomas.abraham at linaro.org>
> ---
>  .../devicetree/bindings/mmc/synposis-dw-mshc.txt   |   85 +++++++++
>  drivers/mmc/host/dw_mmc-pltfm.c                    |   24 +++
>  drivers/mmc/host/dw_mmc.c                          |  181 +++++++++++++++++++-
>  drivers/mmc/host/dw_mmc.h                          |   10 +
>  include/linux/mmc/dw_mmc.h                         |    2 +
>  5 files changed, 296 insertions(+), 6 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
>
> diff --git a/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
> new file mode 100644
> index 0000000..c1ed70e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
> @@ -0,0 +1,85 @@
> +* Synopsis Designware Mobile Storage Host Controller
> +
> +The Synopsis designware mobile storage host controller is used to interface
> +a SoC with storage medium such as eMMC or SD/MMC cards.
> +
> +Required Properties:
> +
> +* compatible: should be one of the following
> +       - synopsis,dw-mshc: for controllers compliant with synopsis dw-mshc.
> +
> +* reg: physical base address of the dw-mshc controller and size of its memory
> +  region.
> +
> +* interrupts: interrupt specifier for the controller. The format and value of
> +  the interrupt specifier depends on the interrupt parent for the controller.
> +
> +# Slots: The slot specific information are contained within child-nodes with
> +  each child-node representing a supported slot. There should be atleast one
> +  child node representing a card slot. The name of the slot child node should
> +  be 'slot{n}' where n is the unique number of the slot connnected to the
> +  controller. The following are optional properties which can be included in
> +  the slot child node.

Since we're talking slots / cards on a bus, I think the addressing
model would be useful here. So in the main controller node:
    #address-cells = <1>;
    #size-cells = <0>;

And then each slot would need a reg property and possibly unit address:

   slot {
        reg = <0>;
        ...
   };

(unit addresses on the slots are only needed if they can't be
disambiguated by name, so not needed if you only have one slot).


-Olof