Réf. : [Linux-usb-users] Re: USB/HID UPS issue (was Re: USB scanner issue)

[arnaud.quette@mgeups.com]

Hi Reg,

> I havent anything to add to your comments, except to make sure you saw
> my comments about USB/HID problems that I have encountered with a UPS.
>
> Since the message was short, I reproduce it here:

Fine as I seem to have missed it.

---

>...
>    (1) When doing a read to get hiddev_event structures, 2.4 only
>    gave the 'real' events from the device that one expected.
>    Under 2.6.0-testx there are several ZERO event structures/sec
>    where the entire structure is ZERO, both hid and value.
>
>    For the current code there may be a 'real' event every few
>    seconds, and 5-10 of these zero events/sec.  I have no
>    idea where they are coming from.
>

I have logged this in bugzilla for some times, but didn't had
time to go deeper (http://bugzilla.kernel.org/show_bug.cgi?id=795)
Eric Penner also added: http://bugzilla.kernel.org/show_bug.cgi?id=1048

>    (2) In one thread the code does a select, followed by a read if
>    data is available.  If one just 'falls thru' to the read with
>    the few lines of code it takes to do the checking, one gets
>    up to 45000 messages/minute (750/sec) reading:
>
>        kernel: drivers/usb/input/hid-core.c: control queue full
>
>    If one puts a 1/10sec sleep between these two commands, the
>    error messages go away.
>
>Anyone know anything about either of these errors?
>Or how to report them to the USB people if you cant post to the USB lists?

About the "control queue full", Vojtech once made a patch  (I should still have
it somewhere. If you want to test it, tell me so...)

Lastly, the best way to report is still to mail to usd-users and usb-devel
lists. Otherwise, the above mentionned Linux' bugzilla is a good way too.

Arnaud