On Fri, May 18, 2018 at 6:53 PM, Aris Aris <father.aris@xxxxxxxxx> wrote: > Hi, > > You could try bitbanging any availiable peripheral(i.e gpio) from each > system at the callbacks and have a logic analyzer measuring and reporting > time delay. Thank you very much Aris for this information. I am fairly new to sound sub system, I’m glad if you can point me on the callbacks. Does the sound driver will be notified aplay\arecord open via “snd_xxx_open(struct snd_pcm_substeam *substream)” callback? Which callbacks of sound driver will tell when it received first and last audio frames\samples? > > Best regards, > > Aris > > On Fri, May 18, 2018 at 3:37 PM, Muni Sekhar <munisekharrms@xxxxxxxxx> > wrote: >> >> [ Please keep me in CC as I'm not subscribed to the list] >> >> Hi All, >> >> I am trying to characterize the audio synchronization between two >> systems. There is a mechanism to route audio between two systems, we >> run ‘aplay’ at one system and ‘arecord’ in other system. >> >> We need to measure the time difference when audio sample is out at one >> port and arriving at another port in different system. >> >> I plan to add printk’s in “struct snd_pcm_ops” call backs, but does >> these call backs tells when it received first and last audio >> frames\samples? >> >> Or else please suggest any other best method. >> >> >> -- >> Thanks, >> Sekhar >> >> _______________________________________________ >> Kernelnewbies mailing list >> Kernelnewbies@xxxxxxxxxxxxxxxxx >> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > > -- Thanks, Sekhar _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
