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From: Wilko Bulte <wilko@yedi.iaf.nl>
Message-Id: <199605181800.UAA21673@yedi.iaf.nl>
X-Organisation: Private FreeBSD site - Arnhem - The Netherlands
Subject: limitation in st.c, should not be there?
To: FreeBSD-hackers@freebsd.org (FreeBSD hackers list)
Date: Sat, 18 May 1996 20:00:47 +0200 (MET DST)
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Hi there,

In 2.1R st.c there is a line that reads:

#define SCSI_2_MAX_DENSITY_CODE 0x17    /* maximum density code specified
                                         * in SCSI II spec. */

In it's own right this is OK, but it also is a (unwanted??) limitation.
I stumbled across it when I wanted to set my DLT drive to use 
hardware compression. It can be set to do compression using 0x81 as
density. This is of course vendor specific, and not according to SCSI-2
(as far as I can see).

On the other hand the driver effectively blocks you in setting up the drive.

Is there any reason to keep this check in the st.c? If you send an invalid
(for that particular tape device) value you will get a reject anyway,
flagging an invalid request.

Comments?
_     __________________________________________________________________________
 |   / o / /  _   Wilko Bulte             email: wilko@yedi.iaf.nl
 |/|/ / / /( (_)  Private FreeBSD site  - Arnhem - The Netherlands
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