Re: USB/DVB - Old Technotrend TT-connect S-2400 regression tracked down

From: David
Date: Mon May 25 2009 - 14:47:17 EST


David wrote:
> Alan Stern wrote:
>
>> Okay, here's a patch for you to try. It refreshes the toggle setting
>> in a linked but otherwise idle QH when a new URB is queued.
>>
>> Alan Stern
>>
>>
>> Index: usb-2.6/drivers/usb/host/ehci-q.c
>> ===================================================================
>> --- usb-2.6.orig/drivers/usb/host/ehci-q.c
>> +++ usb-2.6/drivers/usb/host/ehci-q.c
>> @@ -88,7 +88,7 @@ static inline void
>> qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd)
>> {
>> /* writes to an active overlay are unsafe */
>> - BUG_ON(qh->qh_state != QH_STATE_IDLE);
>> + BUG_ON(qh->qh_state != QH_STATE_IDLE && !list_empty(&qh->qtd_list));
>>
>> qh->hw_qtd_next = QTD_NEXT(ehci, qtd->qtd_dma);
>> qh->hw_alt_next = EHCI_LIST_END(ehci);
>> @@ -971,7 +971,13 @@ static struct ehci_qh *qh_append_tds (
>> /* can't sleep here, we have ehci->lock... */
>> qh = qh_make (ehci, urb, GFP_ATOMIC);
>> *ptr = qh;
>> + } else if (list_empty(&qh->qtd_list)) {
>> + /* There might have been a Clear-Halt while the QH
>> + * was linked but empty.
>> + */
>> + qh_refresh(ehci, qh);
>> }
>> +
>> if (likely (qh != NULL)) {
>> struct ehci_qtd *qtd;
>>
>>
>>
>>
> No luck I'm afraid (although there now appear to be 2 timeouts, not
> one). I'm going to follow up on the laptop and get a USB log.
>
USB log post-patch attached. Thanks for all the effort so far!

David

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