Re: [REGRESSION] "USB: use kfifo to buffer usb-generic serial writes" causes gobi_loader to hang

From: Anssi Hannula
Date: Sun Feb 21 2010 - 18:13:48 EST


On maanantai 22 helmikuu 2010 01:06:36 Anssi Hannula wrote:
> On maanantai 22 helmikuu 2010 00:12:36 Oliver Neukum wrote:
> > Am Sonntag, 21. Februar 2010 22:42:12 schrieb Anssi Hannula:
> > > And of course this doesn't explain why it hangs (and the WARNING) if I
> > > remove the sleep calls I added in gobi_loader.
> >
> > Please tell us where you put a delay.
>
> As I said earlier, the delay was put *before* most of the data gets
> written.
>
> More specifically, I inserted a delay of one second between transmission of
> magic1 and magic2, one between magic2 and magic3, and one between magic3
> and the first firmware file.
>
> If I additionally insert a one-second delay before the fd is closed, I get
> this usbmon log:
> http://stuff.onse.fi/gobi2000/gobi-regression5.mon.log
>
> The firmware upload is still unsuccessful.

If I use the option driver instead of qcserial, the firmware upload is always
successful (without any added delays needed). The usbmon log for that case can
be found here:
http://stuff.onse.fi/gobi2000/gobi-regression6.mon.log

--
Anssi Hannula
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