Hi everybody, On Sunday 13 May 2007, Greg KH wrote: > On Sat, May 12, 2007 at 12:44:38AM -0700, Pete Zaitcev wrote: > > On Fri, 11 May 2007 23:23:18 -0700, Greg KH <[EMAIL PROTECTED]> wrote: > > > I thought that you needed to do something with this value pretty > > > quickly, and that by the time you were able to send something back into > > > the kernel, the value would be not correct anymore. But if this is > > > really just like a timestamp, then ok, I have no objection other than > > > it needs to be correct for all host controllers. > > > > Greg, I'm sorry if I'm wrong, but it looks you missed the funny part. > > Danny's device remembers the value that HC circulated in the SOF frame. > > It then supplies that value alongside some data it returns. By reading > > the "current" frame number from HC, Danny's application can tell > > how many frames back, approximately, these data were generated > > (this is not the time when it was transferred across USB). > > Ah, yeah, I missed that. > > If Alan fixes up the hcds, I'll take the patch.
Following up on this, would it be possible to know the host timestamp (gettimeofday) associated with the last SOF token ? I'm also working with devices that would benefit from clock synchronisation (device clock, SOF counter and host clock). The device reports the relationship between the device clock and the SOF counter, but I currently have no easy way to get the relationship between the SOF counter and the host clock. Regards, Laurent Pinchart ------------------------------------------------------------------------- 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
