[Qemu-devel] Re: [5048] husb: support for USB host device auto connect (Max Krasnyansky)

[Jan Kiszka <jan.kiszka@siemens.com>]

Jan Kiszka wrote:
> Anthony Liguori wrote:
>> Revision: 5048
>>           http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=5048
>> Author:   aliguori
>> Date:     2008-08-21 19:28:55 +0000 (Thu, 21 Aug 2008)
>>
>> Log Message:
>> -----------
>> husb: support for USB host device auto connect (Max Krasnyansky)
>>
>> QEMU can now automatically grab host USB devices that match the filter.
>> For now I just extended 'host:X.Y' and 'host:VID:PID' syntax to handle
>> wildcards. So for example if you do something like
>>    usb_add host:5.*
>> QEMU will automatically grab any non-hub device with host address 5.*.
>>
>> Same with the 'host:PID:*', we grab any device that matches PID.
>>
>> Filtering itself is very generic so we can probably add more elaborate
>> syntax like 'host:BUS.ADDR:VID:PID'. So that we can do 'host:5.*:6000:*'.
>>
>> Anyway, it's implemented using a periodic timer that scans host devices
>> and grabs those that match the filter. Timer is started when the first
>> filter is added.
>>
>> We now keep the list of all host devices that we grabbed to make sure that
>> we do not grab the same device twice.
>>
>> btw It's currently possible to grab the same host device more than once.
>> ie You can just do "usb_add host:1.1" more than once, which of course does
>> not work. So this patch fixes that issue too.
>>
>> Along with auto disconnect patch that I send a minute ago the setup is very
>> seamless now. You can just allocate some usb ports to the VMs and plug/unplug
>> devices at any time.
>>
>> Signed-off-by: Max Krasnyansky <maxk@kernel.org>
>> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
>>
> 
> ...
> 
>> Modified: trunk/vl.c
>> ===================================================================
>> --- trunk/vl.c	2008-08-21 19:27:48 UTC (rev 5047)
>> +++ trunk/vl.c	2008-08-21 19:28:55 UTC (rev 5048)
>> @@ -5747,6 +5747,32 @@
>>      free_usb_ports = port;
>>  }
>>  
>> +int usb_device_add_dev(USBDevice *dev)
>> +{
>> +    USBPort *port;
>> +
>> +    /* Find a USB port to add the device to.  */
>> +    port = free_usb_ports;
>> +    if (!port->next) {
>> +        USBDevice *hub;
>> +
>> +        /* Create a new hub and chain it on.  */
>> +        free_usb_ports = NULL;
>> +        port->next = used_usb_ports;
>> +        used_usb_ports = port;
>> +
>> +        hub = usb_hub_init(VM_USB_HUB_SIZE);
>> +        usb_attach(port, hub);
>> +        port = free_usb_ports;
>> +    }
>> +
>> +    free_usb_ports = port->next;
>> +    port->next = used_usb_ports;
>> +    used_usb_ports = port;
>> +    usb_attach(port, dev);
>> +    return 0;
>> +}
>> +
>>  static int usb_device_add(const char *devname)
>>  {
>>      const char *p;
>> @@ -5787,26 +5813,7 @@
>>      if (!dev)
>>          return -1;
>>  
>> -    /* Find a USB port to add the device to.  */
>> -    port = free_usb_ports;
>> -    if (!port->next) {
>> -        USBDevice *hub;
>> -
>> -        /* Create a new hub and chain it on.  */
>> -        free_usb_ports = NULL;
>> -        port->next = used_usb_ports;
>> -        used_usb_ports = port;
>> -
>> -        hub = usb_hub_init(VM_USB_HUB_SIZE);
>> -        usb_attach(port, hub);
>> -        port = free_usb_ports;
>> -    }
>> -
>> -    free_usb_ports = port->next;
>> -    port->next = used_usb_ports;
>> -    used_usb_ports = port;
>> -    usb_attach(port, dev);
>> -    return 0;
>> +    return usb_device_add_dev(dev);
>>  }
>>  
>>  int usb_device_del_addr(int bus_num, int addr)
> 
> Same complaint here: Please avoid adding new warnings, it makes tracking
> my own regressions only harder. ;)
> 
> Jan
> 
> -------
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>  vl.c |    1 -
>  1 file changed, 1 deletion(-)
> 
> Index: b/vl.c
> ===================================================================
> --- a/vl.c
> +++ b/vl.c
> @@ -5779,7 +5779,6 @@ static int usb_device_add(const char *de
>  {
>      const char *p;
>      USBDevice *dev;
> -    USBPort *port;
>  
>      if (!free_usb_ports)
>          return -1;

It's still throwing a warning at me...

Jan

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