Re: composite gadget support
Alan Stern <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
On Wed, 31 Oct 2007, Ramirez-Ortiz, Jorge wrote: > Hi Alan > Yes we are saying the same thing despite my errors ..apologies. > Rats...why do you think the specification doesn't cover for gadget auto > configuration? There is no such thing. When a USB device is first attached to a host, it must start in configuration 0 (the unconfigured state) and remain like that until the host sends it a Set-Configuration command. > I can see many gadgets with user interfaces that would > like to provide different functionalities to different users depending > on a password for instance... Are you talking about a password typed into the host or a password typed into the gadget? If you mean a password typed into the host then the different functionalities must be provided by host software, since the gadget won't be aware of the password. If you mean a password typed into the gadget then there's a simple approach. When the password is typed in, the gadget disconnects from the host and then reconnects. When the host enumerates it, the gadget presents descriptors for the capabilities associated with the password. You can have several different sets of descriptors stored, and use whichever one is appropriate for the particular user. But note that you must not switch descriptors without disconnecting so the host can learn about the new descriptors. Alan Stern ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel