Re: [RFC PATCH v2 14/22] dt-bindings: usb: dwc3: Add snps,num-hc-interrupters definition

[Krzysztof Kozlowski]

On 26/01/2023 04:14, Wesley Cheng wrote:
> Add a new definition for specifying how many XHCI secondary interrupters
> can be allocated.  XHCI in general can potentially support up to 1024
> interrupters, which some uses may want to limit depending on how many
> users utilize the interrupters.

I cannot find in the code any user of this. Your next patch stores it,
but which other patch uses stored value?

What I still don't get how is this exactly hardware property, not policy
or driver choice.

> 
> Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
> ---
>  Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> index 6d78048c4613..4faaec9655e0 100644
> --- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> +++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> @@ -349,6 +349,18 @@ properties:
>      items:
>        enum: [1, 4, 8, 16, 32, 64, 128, 256]
>  
> +  snps,num-hc-interrupters:
> +    description:
> +      Defines the maximum number of XHCI host controller interrupters that can
> +      be supported.  The XHCI host controller has support to allocate multiple
> +      event rings, which can be assigned to different clients/users.  The DWC3
> +      controller has a maximum of 8 interrupters.  If this is not defined then
> +      the value will be defaulted to 1.  This parameter is used only when
> +      operating in host mode.
> +    $ref: /schemas/types.yaml#/definitions/uint8
> +    minimum: 1
> +    maximum: 8

default: 1

> +
>    port:
>      $ref: /schemas/graph.yaml#/properties/port
>      description:

Best regards,
Krzysztof