On Tue, Apr 24, 2007 at 07:58:33AM +0200, Oliver Neukum wrote: > Am Dienstag, 24. April 2007 01:32 schrieb Greg KH: > > On Tue, Apr 24, 2007 at 01:24:02AM +0200, Oliver Neukum wrote: > > > Am Dienstag, 24. April 2007 00:35 schrieb Greg KH: > > > > > This suggests that usbfs2 should have special "interface" files as > > > > > well as > > > > > a special "device" file and "endpoint" files. > > > > > > > > Nah, I don't think that will be needed. > > > > > > 1. Interfaces have properties, namely the setting > > > > Yes, which we should be able to control through the control endpoint > > with an ioctl, right? > > No, because then we'd have to continue giving access to the whole > device if we want to drive only an interface. The 0 endpoint must be > replicated for each interface, which is in effect the "interface" file > Alan is talking about. Plus, there are situation where some requests > to endpoint 0 must fail and others must work. > > > > 2. We cannot operate solely at the level of the endpoint > > > We must know which requests are affected when an interface > > > is affected, eg. reset cannot restore the altsetting. This cannot work > > > at the endpoint level because endpoint 0 is shared. We cannot drop > > > claiming an interface as is done in the current usbfs. > > > > Once you open an endpoint that is not endpoint 0 that would signify that > > the interface is then "claimed" as far as the kernel goes, right? > > That's not enough. The kernel must have a notion of _who_ owns the > interface. As a task may own several interfaces, the action must be > explicit. Besides, an interface is not required to have endpoints, nor > should a task be required to open an endpoint just for show. > > You are designing a kludge.
"I'm" not designing it, I just offered up my initial ideas, others are trying to run with them and see if they are crap or not. Most likely, crap, but hopefully they will have figured it out by the time we get it into the kernel tree :) Any help you can provide them will probably be greatly appreciated. thanks, greg k-h ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
