Re: [PATCH 4/6] drivers:misc: sources for Init manager module

[Pavan Savoy <pavan_savoy@yahoo.co.in>]

--- On Wed, 24/3/10, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:

> From: Alan Cox <alan@lxorguk.ukuu.org.uk>
> Subject: Re: [PATCH 4/6] drivers:misc: sources for Init manager module
> To: "Pavan Savoy" <pavan_savoy@yahoo.co.in>
> Cc: "Marcel Holtmann" <marcel@holtmann.org>, "Greg KH" <gregkh@suse.de>, "PavanSavoy" <pavan_savoy@ti.com>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
> Date: Wednesday, 24 March, 2010, 10:33 PM
> Ok I had a brief dig
> 
> Making a driver able to say "and open me in this ldisc" is
> about ten
> lines of code to the core tty layer if that.
> 
> There is one caveat - the actual ldisc attach method for an
> ldisc attach
> isn't allowed to fail the attach. That's something we
> eventually need to
> fix anyway.
> 
> Otherwise it doesn't look too scary and it would occur when
> the user
> opened the file not when the device was created.

So as I understand the user-space application/daemon should do an open on the TTY and then do nothing ?
Somewhere down the line, the driver may do a tty_set_ldisc, and use it the way it wants to ?

Isn't there a mechanism for the tty_set_ldisc to do what _open does ?
I mean there might be plenty of devices on UART which might not need /dev/tty at all ? i.e An App need not open for a ldisc to be installed.


> 
> Alan
> 


      The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. http://in.yahoo.com/