Quirks

[Tino Engel]

Hi Petter,

On Wed, 9 Jul 2008 23:44:08 +0200
Hans Petter Selasky <hselasky at c2i.net> wrote:


> Hi Tino,
> 
> On Wednesday 09 July 2008, Tino Engel wrote:
> > Dear all,
> >
> > I had the chance to write my first Quirk-PR and therefore took some
> > time looking at the FreeBSD usb system.
> > I am thinking that the solution there is is not the ideal
> > one. Through mailing list discussions I read, I also have the
> > impression, that the usb part of the cam subsystem is kind of a
> > problem child.
> > I read through parts of the usb code and am kind of understanding
> > it. So I am trying to make an attempt to help improving it. That
> > means, that I would like to discuss some ideas and in case this is
> > wanted, volunteer to do some coding.
> >
> > What I was thinking so far is:
> >
> > Since Windows and Linux can handle most of the the devices FreeBSD
> > needs a quirk for out of the box, and at least in the case of
> > linux, I believe they do not hold all quirks in a db, there must be
> > a way of doing it.
> >
> > My idea so far is to do something like this:
> > - When a usb device is connected, try to use it without quirks.
> > - If it stalls, cache device id data
> > - Then emulate a disconnect/connect
> 
> Yes, this is possible. But unfortunately some devices are very crappy
> and even if you do a USB BUS reset, they will malfunction after the
> invalid command, simply because the USB software on the dongle has
> crashed :-) Or the endpoint state is not correct.
> 
> > - Then try all permutations of possible quirks (most common to less
> > common?) for the device
> > - As soon as one permutation causes device not to stall -> done
> 
> I assume that you are thinking about Mass Storage devices. You might
> be interested in looking at:
> 
> http://www.selasky.org/hans_petter/isdn4bsd/sources/src/sys/dev/usb2/core/usb2_msctest.c
> 

Yes, your Assumption is right. I am about mass storage.

I have looked your at the code. 
As far as I can see the whole package it is meant as a replacement for
the existing usb-driver in freebsd. (Correct me if I am wrong)
But it seems to be installed just as an addon... How does that
interfere with what is existing in freebsd?

Can you please tell me a little more about the plans of merging this
into freebsd?

> >
> > Anyhow my knowledge concerning the topic is not too in-deep, but I
> > would be happy to gather some feedback concerning my idea and maybe
> > about other approaches in this area.
> 
> How much time are you willing to spend on this ?
> 
> --HPS

I am willing to spend about 5h a week, from time to time more. (depends
on things like job-workload, weather, etc...) 
Anyhow I am more into doing than into planning, so i would be happy to
help, when some surroundings have been clarified to me.
(i.e. develop on top of what, what to do exactly, etc...)

Greez, Tino