Following several tests we did with qemu trunk,
Isochronous transfer seems to be broken with the head of qemu.
following Os (targets):
kernel ( 2.6.26-1 (i386), 2.6.27 (ARM) )
On our host we are using Gentoo
with 2.6.23 and 2.6.27 kernel.
Following USB devices were tested:
2.0 logitech webcams
-Terratec USB2.0 Cynergy hybrid XS FM tuner.
OHCI and UHCI configurations were tested in i386 target.
Only OHCI was tested
in ARM target.
In all these configurations, it was never
to initiate isochronous USB transfer. It was possible to enumerate the devices
but as soon as isochronous packets were used, the procedure failed. It means for
example that no picture was retrieved from the webcams, and no audio data was
retrieved from FM tuner.
It is important to mention that all theses
devices perfectly work on our host.
After some search in this maling list
archives, it seems that no work has been made on these aspects since Arnon
Gilboa sent some patches more than one year ago. Am I wrong?
So It would
be very useful for us to have a feedback from the community on this
Has someone met the same problems? Has someone investigated this
Is someone regularly using this feature?
How can we