Greetings,
We recently upgraded from 2.4.24 to 2.4.28 and the problem described
below appeared. I have tested it on 2.4.30 and the fault still exists.
It is something to do with usb serial. We are actually using the
ftdi_sio module but a quick diff suggests it hasn't changed much. I am
not 100% sure what is going on but we are sending out various short
commands (11 bytes) to an external device. Most work just fine but one
using one sequence seems to cause the driver to loop and continually
send out the same command. The application keeps sending other commands
but eventually the write () blocks and that's that.
Examining the packet that caused the problem showed it was very similar
to the others but it contained 0x0a. This obviously stuck out as being a
candidate for some sort of translation problem.
I also built a 2.4.28 kernel with the ftdi_sio and usbserial code from
the 2.4.24 release. It also failed. This was a surprise and I am
wondering of I did it correctly.
I don't have the failing equipment with me here but will return to site
next week. I would appreciate any words of wisdom on the problem.
--
Ian Leonard
Please ignore spelling and punctuation - I did.
From: [email protected]
> We recently upgraded from 2.4.24 to 2.4.28 and the problem described
> below appeared. I have tested it on 2.4.30 and the fault still exists.
[snip]
> Examining the packet that caused the problem showed it was
> very similar
> to the others but it contained 0x0a. This obviously stuck out
> as being a
> candidate for some sort of translation problem.
That's a software flow control character, have you turned off software
flow control?
..Stu
On Thu, 26 May 2005 18:52:10 +0100, Ian Leonard <[email protected]> wrote:
> We recently upgraded from 2.4.24 to 2.4.28 and the problem described
> below appeared. I have tested it on 2.4.30 and the fault still exists.
>[...]
> Examining the packet that caused the problem showed it was very similar
> to the others but it contained 0x0a. This obviously stuck out as being a
> candidate for some sort of translation problem.
The above looks almost too obvious but for this:
> I also built a 2.4.28 kernel with the ftdi_sio and usbserial code from
> the 2.4.24 release. It also failed. This was a surprise and I am
> wondering of I did it correctly.
Did you nail down a scenario which we can debug? Frankly it's not credible
that transplanted usbserial and ftsi_sio would fail to work. I know that
I changed quite a bit between 2.4.24 and 2.4.28, but your experiment
undoes that.
-- Pete