[PATCH v2 3/6] mfd: dt: Add bindings for the Aspeed LPC Host Controller (LPCHC)

Joel Stanley joel at jms.id.au
Thu Nov 3 16:06:29 PDT 2016


On Thu, Nov 3, 2016 at 1:07 AM, Andrew Jeffery <andrew at aj.id.au> wrote:
> The Aspeed LPC Host Controller is presented as a syscon device to
> arbitrate access by LPC and pinmux drivers. LPC pinmux configuration on
> fifth generation SoCs depends on bits in both the System Control Unit
> and the LPC Host Controller.
>
> Signed-off-by: Andrew Jeffery <andrew at aj.id.au>
> ---
>  Documentation/devicetree/bindings/mfd/aspeed-lpchc.txt | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/aspeed-lpchc.txt
>
> diff --git a/Documentation/devicetree/bindings/mfd/aspeed-lpchc.txt b/Documentation/devicetree/bindings/mfd/aspeed-lpchc.txt
> new file mode 100644
> index 000000000000..792651488c3d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/aspeed-lpchc.txt
> @@ -0,0 +1,17 @@
> +* Device tree bindings for the Aspeed LPC Host Controller (LPCHC)

I had to check the data sheet for that acronym. They call the
registers LHC. I somewhat prefer that name, but if you're happy with
it as-is then that's fine.

I assume this is not an issue on the g4/ast2400?

> +
> +The LPCHC registers configure LPC behaviour between the BMC and the host
> +system. The LPCHC also participates in pinmux requests on g5 SoCs and is
> +therefore considered a syscon device.
> +
> +Required properties:
> +- compatible:          "aspeed,ast2500-lpchc", "syscon"
> +- reg:                 contains offset/length value of the LPCHC memory
> +                       region.
> +
> +Example:
> +
> +lpchc: lpchc at 1e7890a0 {
> +       compatible = "aspeed,ast2500-lpchc", "syscon";
> +       reg = <0x1e7890a0 0xc4>;

Where's the 0xc4 come from? I can see 9 registers, which would mean
the length should be 0x24?

Cheers,

Joel



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