On Sun, 13 Mar 2016, Oleksij Rempel wrote: > Am 13.03.2016 um 16:30 schrieb Alan Stern: > > On Sun, 13 Mar 2016, Oleksij Rempel wrote: > > > >> Hallo all, > >> > >> i need to sync device clock with host clock, since device will return > >> SOF counter for each packet i need to use it as reference. Are there any > >> proper way to convert SOF to a host timestamp? > > > > No, there isn't. There is no relationship between the SOF packet > > arrival time or frame number and the host's time. > > > > Alan Stern > > > > Hm... Usb Vidoe Class specification suggest to use Source Time Clock > (some internal clock) value connected with SOF number to get actual > Frame timestamp. At same time bDealy from audio descriptor should be > used to sync audio and video. If i see it correctly, bDelay is expressed > in SOF or milliseconds as well. So if only way to Sync both streams is > SOF, how can it be made? > Is it possible to get at least SOF number of received packet? That depends on the firmware in your device. The host has nothing to do with it. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
