On Thu, 5 Jan 2006, Jeff Lange wrote:

> Alan,
>   That did the trick!  Now what would be really good is if there was a
> module argument that could disable FSBR for pesky devices.  Or maybe a
> way that if the FSBR seems to be failing, to fall back to disabling
> it?

It's not so easy to do either of those things, since it's not easy to tell
which devices are pesky or don't like FSBR.  However the patch below might
be acceptable.  It probably duplicates the way Windows behaves (although I
haven't tested Windows to be sure).  The idea is not to use FSBR until
after a device is enumerated and configured.  Up until now, we've been
using FSBR as soon as the device is addressed.

So this will slow down the enumeration and configuration procedures a 
little, but not enough to matter.  If your device can work with this 
patch, I'll submit it for inclusion in the kernel.

BTW, have you tried connecting the device to a computer with an OHCI host
controller rather than UHCI?  I don't really know how FSBR works with
OHCI, but I think there's no way to turn it off at all.

Alan Stern



Remember to remove the old patch before applying this one.

Index: l2615/drivers/usb/host/uhci-q.c
===================================================================
--- l2615.orig/drivers/usb/host/uhci-q.c
+++ l2615/drivers/usb/host/uhci-q.c
@@ -672,9 +672,9 @@ static int uhci_submit_control(struct uh
        /* Low-speed transfers get a different queue, and won't hog the bus.
         * Also, some devices enumerate better without FSBR; the easiest way
         * to do that is to put URBs on the low-speed queue while the device
-        * is in the DEFAULT state. */
+        * isn't in the CONFIGURED state. */
        if (urb->dev->speed == USB_SPEED_LOW ||
-                       urb->dev->state == USB_STATE_DEFAULT)
+                       urb->dev->state != USB_STATE_CONFIGURED)
                skelqh = uhci->skel_ls_control_qh;
        else {
                skelqh = uhci->skel_fs_control_qh;



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