Re: usbmon packet data format
"Jon Smirl" <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
On 2/27/07, Paolo Abeni <[email protected]> wrote: > On Mon, 2007-02-26 at 21:29 -0500, Jon Smirl wrote: > > I'm looking at the request/response record of a get descriptor zero. > > > > [...] > > > > Response has eight bytes of leading zeros which correspond to the > > eight bytes of the request. > > I'm sorry to see I wasn't able to explain the issue. The usb setup data > (as described in section 9.3 of USB specification 2.0) is present in > each event provided by the kernel and correspond to this 8 bytes. The > setup data is valid (and has to be interpret) only when the setup flag > is set to 0, otherwise it's value is undefined (may always 0, but don't > count on this). I see the setup data on the URB submits and it is getting decoded without problem. I've never seen the setup data filled in on a URB completion. Is it possible for this field to get filled in on an URB completion? If not, let's remove it for completion packets and save a lot of space. That would remove eight bytes from every other packet. > This lead to some waste of space (8 bytes for each event which don't > really carry a setup packet) but lead to a simpler implementation. The > choose was debated during usbmon binary API definition/creation. > > ciao, > > Paolo > > > > -- > Email.it, the professional e-mail, gratis per te: http://www.email.it/f > > Sponsor: > Refill s.r.l. - Prodotti per TUTTE le stampanti sul mercato a prezzi sempre convenienti. Dal 1993, leader nel compatibile di qualità in Italia. > Clicca qui: http://adv.email.it/cgi-bin/foclick.cgi?mid=5188&d=27-2 > -- Jon Smirl [email protected] ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel