On Tue, 19 Dec 2006, Clemens Ladisch wrote: > Alan Stern wrote: > > On Mon, 18 Dec 2006, Mike King wrote: > > > Are endpoint addresses unique across a device ? > > > > > > In other words, can a device with 2 interfaces have an endpoint in > > > each interface that is address 0x81. Or would they have to be > > > distinct, like 0x81 in one and 0x82 in the other one ? > > > > Different interfaces in the same configuration are not allowed to use > > the same endpoint. > > Which doesn't prevent M-Audio from building such devices. > > In this case, the driver has to take care to avoid using these > interfaces > at the same time.
I don't understand this. A USB driver doesn't "use" interfaces; all it does is send packets to various endpoints. It's up to the device to decide what to do with those packets. So for example, if interface 0 and interface 1 both contain endpoint 2-in, and your driver submits a request to transfer 64 bytes from that endpoint, which interface are you "using"? Alan Stern ------------------------------------------------------------------------- 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 _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
