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

[Oza Oza]

On Tue, Aug 8, 2017 at 7:50 PM, Rob Herring <robh+dt@xxxxxxxxxx> wrote:
> Please send bindings to DT list.

Sure, will do that.

>
> 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.
>

ok I will rename this to
brcm,slot-pluggable

>> +
>> +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

will take care.

>
>> +
>> +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
>>