linux-kernel - Re: How do I choose an arbitrary minor number for my tty device?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 23 Nov 2010 23:03:59 +0000
From:	Alan Cox <alan@...rguk.ukuu.org.uk>
To:	Timur Tabi <timur@...escale.com>
Cc:	Greg KH <gregkh@...e.de>, Arnd Bergmann <arnd@...db.de>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Scott Wood <scottwood@...escale.com>,
	Stuart Yoder <stuart.yoder@...escale.com>
Subject: Re: How do I choose an arbitrary minor number for my tty device?

> Are you talking about this:
> 
> static struct tty_driver *ehv_bc_console_device(struct console *co, int *index)
> {
> 	*index = co->index;
> 
> 	return ehv_bc_driver;
> }

Yes.

> I never really understood this function, but almost everyone does the same
> thing, and it seems to work for me.  Looking at console_device(), it appears
> that all of the xxx_console_device functions are called in order until one of
> them returns non-NULL.

*index is the minor number to use - so you can return whichever minor
matches your primary interface

> > I suspect in your case you probably want to attach the primary byte
> > channel to minor 0 in the driver (and reserve it for that), or some
> > similar rule.
> 
> Yes, that's a good idea.  It does simplify things a lot.

It's probably the cleanest and simplest solution and it fits the
"natural" order of things.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/