How to determine link of umass/da devices

Bernd Walter ticso at
Thu Oct 20 03:58:13 PDT 2005

On Wed, Oct 19, 2005 at 09:38:08AM -0600, M. Warner Losh wrote:
> In message: <20051017143356.GA12188 at>
>             Tom Alsberg <alsbergt at> writes:
> : With tools like usbdevs and sysctl, I can find out what USB devices
> : are connected, and also what USB drivers handle them (so I can see,
> : for example, that there is a SanDisk Cruzer Micro connected to port 2
> : in bus 3 and the umass driver under it).
> You can find this out best via the devinfo interface.
> : I can also find out what da devices there are using camcontrol.
> Right.  cam doesn't hook the da devices into the device tree.
> : However, how can I find out which da device was assigned to which
> : umass/usb device?
> Generally, you can't.  There's not really an interface to get this
> information.  devinfo assumes that things like disk drives would be in
> the device tree and except for cam, all other drivers conform to this
> world view.  There's some efforts to update and lock cam which I think
> will rectify this.

Not absolutely technicaly correct, but currently one can savely assume
that the umass-sim number from camcontrol devlist -v is identic with the
umass number from devinfo.
This assumption likely won't hold forever.

B.Walter                   BWCT      
bernd at                                  info at

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