Re: [PATCH 14/16] USB: Add usbfs ioctl to get the frame number
Pete Zaitcev <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Organization | Red Hat, Inc. |
| Message-ID | <[email protected]> |
On Sat, 12 May 2007 15:40:45 -0400 (EDT), Alan Stern <[email protected]> wrote: > > timestamp, which would not depend on HC implementing SOF number > > as a monotonously increasing counter (I think, it's not guaranteed). > The frame numbers are guaranteed to be monotonically increasing until they > roll over from 2047 to 0 (see 8.3.3, 8.4.3, and 10.2.3 in the USB spec). I see, you're right, of course. I only looked at 8.4.3, and it was somewhat vague. The 10.2.3 places stronger restrictions on the way numbers are generated, although oddly enough it alows a host to keep wider counters than are needed. -- Pete ------------------------------------------------------------------------- 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/ _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel