On 05/13/2012 07:45 PM, plutek wrote: > From: Robin Gareus <robin@xxxxxxxxxx> > Date: Sun, 13 May 2012 08:57:26 +0200 > >> On 05/13/2012 03:13 AM, plutek wrote: >>> From: Karsten Wiese <fzuuzf@xxxxxxxxxxxxxx> >>> Date: Sat, 12 May 2012 23:18:22 +0200 >>> >>>> 2012/5/12 Clemens Ladisch <clemens@xxxxxxxxxx>: >>>>> plutek wrote: >>>>>> i've been running AVLinux5.0.3 on a ThinkPad T61p for a while now.... >>>>>> with an ART USB Dual Tube Pre, i can run Jack at 64 frames, 2 periods >>>>>> >>>>>> now i've got a new ThinkPad T520, and if i start jack on USB at 64*2 >>>>>> i get hundreds of xruns in seconds. >>>>> >>>>> Both machines run (I assume) the same software? Then the problem is >>>>> with the hardware, or its drivers. >>>>> >>>>> Please show the output of lspci and the contents of /proc/interrupts. >>>>> >>>> >>>> Thinkwiki says its got a QM67. That does USB 1.1 via the "Rate >>>> matching hub" and EHCI. >>>> I guess linux's hub driver is the culprit. >>> >>> hmmmm.... shame.... lenovo specs said, of course, "USB 2.0". >>> mrph. >>> >>> any way around this currently? >> >> yes, >> >> http://lists.linuxaudio.org/pipermail/linux-audio-dev/2010-October/029511.html > > after i do: > > # cd /sys/bus/pci/drivers/ehci_hcd/ > # echo -n 0000:00:1d.0 > unbind > > ...the USB audio device no longer shows up in qjackctl. > > did i misunderstand? No, not that I can tell. "0000:00:1d.0" is the USB hub/controller, right? The idea is to use the uhci_hcd (USB1) driver instead of ehci_hcd (USB2). -- Maybe the module is not loaded? `lsmod | grep uhci_hcd` `ls /sys/bus/pci/drivers/uhci_hcd/` If they're modules: `rmmod ehci_hcd; modprobe uhci_hcd`; that'll force all USB ports into 1.X mode; may be worth a try before playing with dedicated per port bindings. Anyway, there might be something else going on: as both Karsten and Clemens noted, these "Intel Corporation Cougar Point [..] controllers use a different driver" and "There have been fixes recently. Try updating the kernel." robin _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
