Implementing isochronous transfers in hw/hcd-ohci.c

[Programmingkid]

Hi Gerd,

Howard and I were talking about USB audio problems with Mac OS guests. We think 
the issue might be with frames being sent to the USB audio card too soon. My 
guess is only one frame is suppose to be transmitted every 1 millisecond. I was 
also reading the todo notes in the file hw/hcd-ohci.c. This is what it says:

 * TODO:
 *  o Isochronous transfers
 *  o Allocate bandwidth in frames properly
 *  o Disable timers when nothing needs to be done, or remove timer usage
 *    all together.
 *  o BIOS work to boot from USB storage
*/

Do you think implementing isochronous transfers would fix the audio problems 
Mac OS guest are experiencing?