Re: [Qemu-devel] [Xen-devel] [PATCH] libxl: Spice usbredirection support for upstream qemu

[Paolo Bonzini <pbonzini@redhat.com>]

----- Messaggio originale -----
> Da: "Fabio Fantoni" <fabio.fantoni@m2r.biz>
> A: "Paolo Bonzini" <pbonzini@redhat.com>
> Cc: "Andreas Färber" <afaerber@suse.de>, "Stefano Stabellini" <stefano.stabellini@eu.citrix.com>,
> xen-devel@lists.xensource.com, "Wei Liu" <wei.liu2@citrix.com>, "Ian Campbell" <Ian.Campbell@citrix.com>, "Ian
> Jackson" <Ian.Jackson@eu.citrix.com>, qemu-devel@nongnu.org, "Hans de Goede" <hdegoede@redhat.com>,
> spice-devel@lists.freedesktop.org
> Inviato: Venerdì, 5 luglio 2013 10:42:30
> Oggetto: Re: [Xen-devel] [PATCH] libxl: Spice usbredirection support for upstream qemu
> 
> Il 04/07/2013 22:09, Paolo Bonzini ha scritto:
> > Il 04/07/2013 19:17, Andreas Färber ha scritto:
> >> Also if at some point you try to use, e.g., q35 rather than i440fx
> >> machine, it might have EHCI by default and the snippet would be
> >> instantiating a duplicate one. I.e., the three levels of dependency
> >> could be separated more clearly: PCI, USB, redirection.
> > At least you could start specifying the USB desired version (1.1, 2.0
> > with companion controllers, 3.0) as an extension of the "usb=1" that is
> > already supported.
> >
> > Paolo
> 
> Thanks and sorry, I found only now that is working also with only
> -device usb-ehci,id=usb.
> I'll post a new patch version.

With only the EHCI you might have problems redirecting USB 1.1 devices.
The EHCI+UHCI magic is the right thing to do for USB 2.0 support on x86.

What Andreas and I were suggesting was to split the patch in two parts:
first adding support for USB 2.0/3.0, and only then adding redirection
(perhaps with the possibility to customize how many redirected devices
to support).

Paolo