Re: [PATCH 2/2] PCI: iproc: Add optional brcm,pci-hotplug

[Rob Herring]

Please send bindings to DT list.

On Mon, Aug 7, 2017 at 11:44 PM, Oza Pawandeep <oza.oza@xxxxxxxxxxxx> wrote:
> Add description for optional device tree property
> 'brcm,pci-hotplug' for PCI hotplug feature.
>
> Signed-off-by: Oza Pawandeep <oza.oza@xxxxxxxxxxxx>
> Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx>
>
> diff --git a/Documentation/devicetree/bindings/pci/brcm,iproc-pcie.txt b/Documentation/devicetree/bindings/pci/brcm,iproc-pcie.txt
> index b8e48b4..a3bad24 100644
> --- a/Documentation/devicetree/bindings/pci/brcm,iproc-pcie.txt
> +++ b/Documentation/devicetree/bindings/pci/brcm,iproc-pcie.txt
> @@ -72,6 +72,29 @@ Optional properties:
>  - brcm,pcie-msi-inten: Needs to be present for some older iProc platforms that
>  require the interrupt enable registers to be set explicitly to enable MSI
>
> +Optional properties:
> +- brcm,pci-hotplug: PCI hotplug feature is supported.

I think we should make this a common property. We already have
"ibm,slot-pluggable", so I'd propose "slot-pluggable".

There's also "hotpluggable" for memory nodes defined, so we could
reuse that here.

> +
> +If the brcm,pcie-hotplug property is present, the following properties become
> +effective:
> +
> +- brcm,prsnt-gpio: Array of gpios, needs to be present if Hotplug is supported.

prsnt-gpios

> +
> +PCI hotplug implementation is SOC/Board specific, and also it depends on
> +how add-in card is designed (e.g. how many present pins are implemented).
> +
> +If x8 card is connected, then it might be possible that all the
> +3 present pins could go low, or at least one pin goes low.
> +
> +If x4 card is connected, then it might be possible that 2 present
> +pins go low, or at least one pin goes low.
> +
> +Example:
> +brcm,prsnt-gpio: <&pca9505 32 1>, <&pca9505 33 1>;
> +This is x4 connector: monitoring max 2 present lines.
> +brcm,prsnt-gpio: <&pca9505 32 1>, <&pca9505 33 1>, <&pca9505 34 1>;
> +This is x8 connector: monitoring max 3 present lines.
> +
>  Example:
>         pcie0: pcie@18012000 {
>                 compatible = "brcm,iproc-pcie";
> --
> 1.9.1
>