Re: [PATCH] tty: Added a CONFIG_TTY option to allow removal of TTY

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

On Thu, 23 Aug 2012 18:14:48 -0700
Joe Millenbach <jmillenbach@gmail.com> wrote:

> ---------- Forwarded message ----------
> From: Joe Millenbach <jmillenbach@gmail.com>
> Date: Thu, Aug 23, 2012 at 5:56 PM
> Subject: Re: [PATCH] tty: Added a CONFIG_TTY option to allow removal of TTY
> To: Alan Cox <alan@lxorguk.ukuu.org.uk>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Alan Cox
> <alan@linux.intel.com>, linux-serial@vger.kernel.org,
> linux-kernel@vger.kernel.org, Josh Triplett <josh@joshtriplett.org>,
> team-fjord@googlegroups.com
> 
> 
> On Tue, Aug 21, 2012 at 6:20 AM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> >
> > ...
> >
> > >  config MOUSE_PS2
> > >       tristate "PS/2 mouse"
> > > +     depends on TTY
> >
> > It shouldn't. It would be good to understand why this occurs.
> 
> 
> If I enable this config option, and turn off TTY I get the below errors.
> 
> drivers/built-in.o: In function `serport_ldisc_read':
> serport.c:(.text+0x1aace6): undefined reference to `tty_name'
> serport.c:(.text+0x1aad57): undefined reference to `tty_name'
> drivers/built-in.o: In function `serport_init':
> serport.c:(.init.text+0x8478): undefined reference to `tty_register_ldisc'
> drivers/built-in.o: In function `serport_exit':
> serport.c:(.exit.text+0xb29): undefined reference to `tty_unregister_ldisc'
> 
> All because MOUSE_PS2 depends on SERIO, just like a lot of entries I
> blocked.  I assume this means I should keep the dependency on TTY.
> Unfortunately, I don't have time to dig deeper for the true cause of the
> dependency right now.

The true cause I think is that serio/serport.c should depend on tty to be
built but the ps/2 mouse bits shouldn't.

Alan