[RFC] status error patch

matthieu castet castet.matthieu at free.fr
Tue May 17 17:17:23 EDT 2005


Roman Kagan wrote:
> On Mon, May 16, 2005 at 11:07:47PM +0200, matthieu castet wrote:
>>Duncan Sands wrote:
>>>On Mon, 2005-05-16 at 11:25 +0200, castet.matthieu at free.fr wrote:
>>>>What I am saying is that -EILSEQ errors happen for each packet that have
>>>>actual_length = 0. So it is happen a lot when you don't download at full 
>>>>(most of the time).
>>>Is this a problem with the modem, or with your host controller?  I guess
>>>you can find out by plugging in some other device with an isoc endpoint.
>>No, other people (at least 4) have the same errors.
> Do you see this with uhci only, or ohci too?
uhci only, I didn't find any tester with ohci.

> which suggests that what you see - zero length iso packets - are
> actually short reads, and should perhaps be treated as no error at all,
> but at the _hcd_ level.
> So I suggest, instead of patching usbatm, patch
> a) uhci-q.c - to ignore short reads like ohci does
> b) ohci-q.c - to propagate iso packet status into urb status
> and see if USB experts are OK with it.  
Ok, I will ask usb expert on linux-usb-devel about that.

> Then usbatm should be fine (BTW
> why do you need to workaround other error conditions but -EILSEQ?).
I was just trying to do something generic.



More information about the Usbatm mailing list