Alan,
I trace into it and found the ohci->hcca->done_head is 0 when
handling OHCI_INTR_WDH interrupt, that will cause the mouse hang. I do
not know why ohci->hcca->done_head will be 0 when ohci_irq() is
triggered. Can you give me some explanation for that? Because from the
2.6.22 kernel source, I found that when entering the ohci_irq()
function, the code will justify if the ohci->hcca->done_head is 0. The
2.6.27 kernel does not have that part code.
So right now , I change the ohci_irq() code as below referring
the 2.6.22 kernel source:
--ints = ohci_readl(ohci, ®s->intrstatus);
++if((ohci->hcca->done_head!=0)
++ && !(hc32_to_cpup(ohci, &ohci->hcca->done_head)
++ & 0x0a)){
++ int = OHCI_INTR_WDH;
++else{
++ ints = ohci_readl(ohci, ®s->intrstatus);
++ ints &= 0xfffffffd;
++ }
Using the ints&0xfffffffd can make the ohci_irq omit the
OHCI_INTR_WDH interrupt if the ohci->hcca->done_head is 0. Now the test
result it fine.
Thanks,
Frank
-----Original Message-----
From: Huang, FrankR
Sent: Tuesday, December 29, 2009 2:45 PM
To: 'Alan Stern'
Cc: USB list
Subject: RE: A question about ohci_irq()
Alan,
In the dl_done_list() function in /drivers/usb/host/ohci-q.c
file,
Before the moment of mouse hang, the dl_reverse_done_list(ohci)
function return value is 0. That will give td a 0 value. After that, the
mouse hang. Why the 0 value will be got from the dl_reverse_done_list?
Thanks,
Frank
-----Original Message-----
From: Alan Stern [mailto:stern@xxxxxxxxxxxxxxxxxxx]
Sent: Tuesday, December 29, 2009 11:41 AM
To: Huang, FrankR
Cc: USB list
Subject: RE: A question about ohci_irq()
On Mon, 28 Dec 2009, Huang, FrankR wrote:
> Alan,
>
> Thanks.I know the reason why the two irq functions are triggered
> at the same time.
> Below is dmesg result.
> I insert a USB mouse and USB disk to the ports.
> And the delay posision for ohci_irq() is :
> ints = ohci_readl(ohci, ®s->intrstatus);
> + udelay(100);
> When the mouse is hang, the ohci_irq() has no response.
What do you mean by "has no response"?
Alan Stern
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
