Re: [PATCH v4 1/2] dt-bindings: usb: add "hub,interval" property

From: Rob Herring
Date: Mon Dec 16 2019 - 10:38:36 EST


On Tue, Dec 03, 2019 at 06:15:36PM +0800, Ikjoon Jang wrote:
> Add "hub,interval" property to usb-device, so hub device can override
> endpoint descriptor's bInterval.
>
> When we know reducing autosuspend delay for built-in HIDs is better for
> power saving, we can reduce it to the optimal value. But if a parent hub
> has a long bInterval, mouse lags a lot from more frequent autosuspend.
> So this enables overriding bInterval for a hard wired hub device only
> when we know that reduces the power consumption.
>
> Signed-off-by: Ikjoon Jang <ikjn@xxxxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/usb/usb-device.txt | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/usb/usb-device.txt b/Documentation/devicetree/bindings/usb/usb-device.txt
> index 036be172b1ae..44bef2ff2704 100644
> --- a/Documentation/devicetree/bindings/usb/usb-device.txt
> +++ b/Documentation/devicetree/bindings/usb/usb-device.txt
> @@ -66,6 +66,9 @@ Required properties for host-controller nodes with device nodes:
> - #size-cells: shall be 0
>
>
> +Optional properties for hub nodes
> +- hub,interval: bInterval of status change endpoint. The range is 1-255.

'hub' is not a vendor.

'b-interval' instead.

Rob