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From: "Serge A. Babkin" <babkin@hq.icb.chel.su>
Message-Id: <199507050727.NAA12463@hq.icb.chel.su>
Subject: Re: Minor for Digiboard driver
To: bde@zeta.org.au (Bruce Evans)
Date: Wed, 5 Jul 1995 13:27:14 +0600 (GMT+0600)
Cc: bde@zeta.org.au, hackers@freebsd.org
In-Reply-To: <199507050634.QAA19621@godzilla.zeta.org.au> from "Bruce Evans" at Jul 5, 95 04:34:47 pm
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> >I took the scheme for minor numbers from sio, the only thing I added
> >is 2 bits of card number :
> 
> >	not_used{14} card_number{2} major{8} sio_like_minor{8}
> 
> >The only problem is that I don't know how to name the special files to
> >be consistent with existing conventions. I know Peter Wemm who wrote
> >Specialix card driver had the same problem and I'll ask him about his
> >decision.
> 
> There doesn't seem to be a good way.  In the cyclades driver I squeezed
> everything into `major{8} sio_like_minor{8}'.  This allows only 2 cards
> of 8 or 16 ports each and there is a gap in the numbering if the first

There may be upto 4 Digiboard cards (according to SCO driver that
has 8-bit minor). Indeed there may be as many cards as many free slots you 
have. Each card may have upto 16 ports. Anyway, if we have 24-bit minors we 
should find some usage for them, huh ? 

> card has only 8 ports.  Eventually we'll have to support either
> ttyd0-ttyd999... (common namespace for all drivers; card number doesn't
> show) and the corresponding cua's and control devices, or
> tty{driver_name}d{device_number_as_in_config}{optional_subdevice_number}.
> I guess we need devfs and both.
> 
> Bruce
>