A kernel level driver is not technically neccesary. I have written
several user-level drivers (for IRIX mostly, but one for Linux) which
issue the apporpriete SCSI-2 commands to control a magazine changer. As
long as the OS in question supports the generic scsi interface, it is a
relativly simple matter since these are documented commands. At present,
I have source code I've written for IRIX to control a HP DDS-2 Autoloader
and a Quantum DLT/4500. Porting to Linux should be a snap. Once you know
the right incantation for a particular OS to send a n-byte command out on
the bus to a particular ID and whatnot, the rest is relativly trivial. You
may have to figure out exactly what command set your device uses --some
devices, like the HP, don't seem to support the MOVE MEDIUM et. al.
commands, and instead use extra arguments to the LOAD/UNLOAD command.
I can give you references to the SCSI-1/2 specification on the web
as well as the source code collection I mentioned before. Anyone who is
interested, just mail me.
I wouldn't recommend writing a kernel level driver for this. But
you might want to bring it up with the folks on linux-scsi (which I am not
subscribed to) and see what they think.
Jeremy
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Jeremy Gilbert grath@gryphon.ccs.brandeis.edu +
Webmaster & UNIX Systems Support grath@mail.cs.brandeis.edu +
Department of Computer Science +
Brandeis University http://gryphon.ccs.brandeis.edu/~grath +
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