On Wed, 4 Jan 2006, Jeff Lange wrote:

> Alan,
>   Yes it did attempt it 4 times,  This error occurs on multiple PC's
> and using different devices (a customer first reported it to us), so I
> would say that it's not a problem with the cable.  I'm just confused
> why it will work in windows and on a 2.4 kernel.  Have the timeout
> values greatly changed from 2.4 to 2.6?  If so, maybe I'll try
> tweaking with that and see if I can get it to work.

I doubt that it's a timeout issue.  There's a good chance it's related to 
Full Speed Bandwidth Reclamation -- your device may not be able to handle 
it.  IIRC one of the UHCI drivers in 2.4 didn't use FSBR, and there 
probably are situations where Windows doesn't use it either (like when a 
device isn't in the CONFIGURED state, although I'm not certain about 
that).

You can try the patch below (for 2.6.15) to turn off FSBR permanently.  If 
it gets your device to work, then good.  Be warned, however, that it will 
greatly reduce throughput -- up to a factor of 20 -- for some kinds of 
devices.

Alan Stern



Index: l2615/drivers/usb/host/uhci-q.c
===================================================================
--- l2615.orig/drivers/usb/host/uhci-q.c
+++ l2615/drivers/usb/host/uhci-q.c
@@ -521,8 +521,10 @@ static void uhci_inc_fsbr(struct uhci_hc
 
        if ((!(urb->transfer_flags & URB_NO_FSBR)) && !urbp->fsbr) {
                urbp->fsbr = 1;
+#if 0
                if (!uhci->fsbr++ && !uhci->fsbrtimeout)
                        uhci->skel_term_qh->link = 
cpu_to_le32(uhci->skel_fs_control_qh->dma_handle) | UHCI_PTR_QH;
+#endif
        }
 }
 



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