> >Do you know if it is ACCEPTABLE to turn of SOF interrupt when there >is nothing to send????
It is possible, but the driver needs a different method to keep track of the frame number. I don't have the hardware specification with me, I think hardware keep tracks the frame number also, all you have to do is read a frame number register. But you have to remember there are still isochronous and interrupt endpoints, those periodic urbs needs to be send in a certain interval. so there might be more than a handful of changes needed to the driver to make this work. >a. would it stop SOF generation towards the function/device? no.. just disable the SOF interrupt in the interrupt enable register. >b. can the driver turns on SOF before having something to send??? >and turn if off after all ack/tarnsactions are completed???? > Yes.. again it is in the interrupt enable register. pei >this is to prevent loading down the cpu for those 1ms interrupt??? > >thanks > > >Pei Liu wrote: >> >> > >> >i am not sure if i understand this driver in depth.... the question >> >i have is who can multiple "packets" be sent within the same frame? >> >> Yes, you can send multiple USB transactions within the same frame. >> >> > >> >the interrupt service routine (hc_interrupt) seems to allow only ONE >> >packet per frame? is this correct??? >> > >> >when xferdone is handled... the sh_done_list is called... if the >> >packet is done... it would return a (-1)... and the interrupt service >> >routine would not start another transaction (sh_schedule_transaction) >> >if the return value is not 0.... that means no packet will go out until >> >next frame? >> > >> >> When USB Done interrupt occurred, it handles the interrupt by calling >> sh_done_list() function. The sh_done_list() returns a code that determines >> if the current USB transactions has completed. If it has not completed, it >> would call the sh_add_packet() to complete current USB transaction. If it >> has completed, then it would call the sh_schedule_trans() routine which will >> schedule the next USB transactions. >> >> Pei > > >------------------------------------------------------- >This SF.NET email is sponsored by: FREE SSL Guide from Thawte >are you planning your Web Server Security? Click here to get a FREE >Thawte SSL guide and find the answers to all your SSL security issues. >http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0026en >_______________________________________________ >[EMAIL PROTECTED] >To unsubscribe, use the last form field at: >https://lists.sourceforge.net/lists/listinfo/linux-usb-devel ------------------------------------------------------- This SF.NET email is sponsored by: FREE SSL Guide from Thawte are you planning your Web Server Security? Click here to get a FREE Thawte SSL guide and find the answers to all your SSL security issues. http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0026en _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
