Re: [Patch RFC 1/4] usb: support device specification via <bus>-<port>

[Juergen Gross <jgross@suse.com>]

On 07/17/2015 08:59 AM, Gerd Hoffmann wrote:
> On Do, 2015-07-16 at 17:47 +0200, Juergen Gross wrote:
>> Today a host usb device can be specified either via <vendor>:<product>
>> or via <bus>.<device> syntax. Add the possibility to specify it via
>> <bus>-<port> as this is needed for the support of xen pvusb backend.
>
> -device usb-host,hostbus=<bus>,hostport=<port> should already do what
> you want.

The problem is I have to add the device while qemu is already running,
so I'm using usb_host_device_open(). To be able to specify the device
via <bus>-<port> I have to add the capability to find the device by
those parameters.

I haven't found another way to achieve this.

>> diff --git a/hw/usb/host-legacy.c b/hw/usb/host-legacy.c
>> index 3cc9c42..526108c 100644
>> --- a/hw/usb/host-legacy.c
>> +++ b/hw/usb/host-legacy.c
>
> I don't think we should extend this.  This exists purely for backward
> compatibility reasons.
>
>> +out:
>>       qdev_prop_set_uint32(&dev->qdev, "hostbus",   filter.bus_num);
>>       qdev_prop_set_uint32(&dev->qdev, "hostaddr",  filter.addr);
>> +    if (filter.port) {
>> +        qdev_prop_set_string(&dev->qdev, "port",  filter.port);
>
> Hmm?  This should have been "hostport", right?

Hmm, yes.


Juergen