USB2 - umass problem

[Hans Petter Selasky]

On Monday 09 February 2009, Nick Hibma wrote:
> > : > By some reason devfs semantic was changed:
> > : > Instead of /dev/cuaU0.[0-2] and /dev/ttyU0.[0-2], I've get
> > : > /dev/cuaU[0-2] /dev/ttyU[0-2] and! /dev/cuau1 /dev/ttyu1
> > : > What is reason for such change (additional port with lowercase 'u'
> > : > and U[0-2] instead of more logical U0.[0-2]) ?
> > :
> > : It is because we are attaching drivers per interface instead of per
> > : device. A new modem unit is allocated every time we find a modem,
> > : simply put. If the modem has multiple instances in an interface,
> > : /dev/cuaU0.[0...] will be created. Else /dev/cuaU... .
> >
> > Generally, we try not to change the details of how a device attaches
> > /dev entries from release to release.  Why the change?
>
> The USB1 u3g driver also attaches to interfaces, but collects all
> interfaces in one go, leaving all unused interfaces available for other
> drivers (e.g. umass) or claims them (to hide the 'driver disks'). It is the
> main reason why I wrote a separate driver in the first place. Otherwise the
> UMTS cards could be treated as serial ports without any port singalling.
>
> It is important to be able to determine in an automated way the 2 or more
> serial ports that belong together. As an example: If you create a router
> box that automatically configures itself depending on the hardware it
> finds, we somehow need to find out which two serial ports are found on each
> GPRS/UMTS card, so we can assign the first one to PPP and the other one to
> our control application.
>

This has been fixed in P4 USB.

--HPS