On Monday 14 May 2007, Pete Zaitcev wrote: > On Mon, 14 May 2007 17:38:56 +0200, Laurent Pinchart <[EMAIL PROTECTED]> wrote: > > 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. > > Why can't you just call the ioctl (I forgot its name) to fetch the > current SOF and then call gettimeofday? Rest assured that the jitter > you get from scheduling is going to be there for any in-kernel > implementation as well.
My implementation would actually be in-kernel, as I'm developing a kernel-space device driver. I was just wondering if the USB host controller issued an interrupt when sending an SOF token. If so, it would be quite easy to store the current host timestamp there. If not, I'll live with it. 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
