On Mon, 8 Nov 2004, Jan Hegner wrote: > Hi, > > our camera device works fine with EHCI controllers. For USB 1.x the device > is slowed down a little bit. This causes no problems at all under windows. > Using Linux 2.6.x kernels the device causes pipe stalls. Not a single frame > can be transmitted without pipe stall. > The device works fine when we increase FSBR_DELAY to 1000. The URB_NO_FSBR > flag does not have any effect at all. > > Does anybody have an idea how to fix that?
The driver may be trying to transfer too much data in a single URB, or trying to queue too many URBs at once. But it seems odd that you get a stall even when trying to receive a single frame. Shouldn't that take less than 50 ms? So increasing FSBR_DELAY from 50 to 1000 shouldn't make any difference. Are you sure the URB_NO_FSBR flag doesn't have any effect? I would expect that setting it would cause things to _stop_ working when FSBR_DELAY is equal to 1000. That's an unpleasant effect, to be sure, but still an effect. Eventually the UHCI driver will be smart enough to handle things a little better. For now you can continue to increase that delay. Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
