Re: [PATCH 02/18] dt-bindings: usb: usb-hcd: Add "wireless" maximum-speed property value

From: Serge Semin
Date: Mon Oct 12 2020 - 17:19:14 EST


On Mon, Oct 12, 2020 at 05:41:50PM +0200, Greg Kroah-Hartman wrote:
> On Sun, Oct 11, 2020 at 08:53:33PM +0300, Serge Semin wrote:
> > On Sun, Oct 11, 2020 at 04:42:36PM +0200, Greg Kroah-Hartman wrote:
> > > On Sun, Oct 11, 2020 at 01:41:05AM +0300, Serge Semin wrote:
> > > > It appears that the "maximum-speed" property can also accept the
> > > > "wireless" value. Add it to the enumeration of the possible property
> > > > values then.
> > > >
> > > > Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
> > > > ---
> > > > Documentation/devicetree/bindings/usb/usb-hcd.yaml | 2 +-
> > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/usb/usb-hcd.yaml b/Documentation/devicetree/bindings/usb/usb-hcd.yaml
> > > > index 815de24127db..e1a82a2b3295 100644
> > > > --- a/Documentation/devicetree/bindings/usb/usb-hcd.yaml
> > > > +++ b/Documentation/devicetree/bindings/usb/usb-hcd.yaml
> > > > @@ -28,7 +28,7 @@ properties:
> > > > isn't passed via DT, USB controllers should default to their maximum HW
> > > > capability.
> > > > $ref: /schemas/types.yaml#/definitions/string
> > > > - enum: ["low-speed", "full-speed", "high-speed", "super-speed",
> > > > + enum: ["low-speed", "full-speed", "high-speed", "wireless", "super-speed",
> > > > "super-speed-plus"]
> > >
> >
> > > Are you sure? wireless usb has been removed from the kernel, where do
> > > you see a user of this? If it's still in there, we need to just drop
> > > it.
> >
> > My decision on suggesting this patch has been based purely on the speed types
> > the USB core API supports and what usb_get_maximum_speed() can return.
> > USB_SPEED_WIRELESS type is one of the possible return values. As I can see
> > aside the rest of the USB speeds the wireless speed is also defined
> > in the kernel USB subsystem. Moreover it is used in some kernel drivers.
> > (See the USB_SPEED_WIRELESS enumeration constant usage.)
> > Are you sure that the wireless speed support has been really removed?
>

> All of the drivers that implement and support this should have been
> removed. Code in the USB core is probably not removed, but patches are
> gladly welcome.
>
> Please do not add new wireless support as it is not going to happen,
> because there are no wireless devices in the world.

Ok. Thanks for clarification. I'll drop this patch then.

-Sergey

>
> thanks,
>
> greg k-h