[cc list restored] On Wed, 2005-03-30 at 14:57 -0800, David Brownell wrote: > Quoth [EMAIL PROTECTED]: > > I think this is connected to a problem people have been reporting on the > > Linux audio lists. With some USB chipsets, USB audio interfaces just > > don't work. There are dropouts even at very high latencies. > > Well, I'd not yet expect USB audio to work over EHCI quite yet, > though one of the patches Greg just posted should help some of > the issues with full speed iso through USB 2.0 hubs. (At least > for OUT transfers as to speakers.) >
This is the exact configuration of one of the users who reported the problem on LAU. Got a pointer to the patch? And what's the issue with IN transfers? > You might consider reporting such issues on the Linux-USB list. > It's been ages since anyone reported such a bug with the OHCI > or UHCI drivers ... probably why folk have assumed there are > no problems there. > OK, good to know. > > Something to consider specifically with audio. That uses the > isochronous transfer mode, reserving USB bandwidth. But I've > certainly seen systems with PCI busses that are severely clogged, > so that the USB controllers have a hard time accessing main > memory. Even a perfectly functional USB stack will have a hard > time with such hardware! Unlikely because it works under Windows. We're not all that far behind however; USB audio on that OS did not really work until XP SP1. Also, if that were a widespread problem we would be seeing problems with PCI devices too. Also please fix the threading in your email client. Lee - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/