| Message ID | 20191203101536.199222-1-ikjn@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | usb: override hub device bInterval with device | expand |
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@chromium.org> > --- > 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
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. + Example: &usb1 { /* host controller */ @@ -75,6 +78,7 @@ Example: hub@1 { /* hub connected to port 1 */ compatible = "usb5e3,608"; reg = <1>; + hub,interval = <8>; }; device@2 { /* device connected to port 2 */
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@chromium.org> --- Documentation/devicetree/bindings/usb/usb-device.txt | 4 ++++ 1 file changed, 4 insertions(+)