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Date: Mon, 22 Aug 2016 23:54:14 +0100
From: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
To: Pavel Machek <pavel@ucw.cz>
Cc: Marcel Holtmann <marcel@holtmann.org>, Rob Herring <robh@kernel.org>,
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Subject: Re: [RFC PATCH 0/3] UART slave device bus
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On Tue, 23 Aug 2016 00:00:17 +0200
Pavel Machek <pavel@ucw.cz> wrote:

> On Mon 2016-08-22 22:32:23, One Thousand Gnomes wrote:
> > > why would we even have it create a /dev/ttyX for these devices in the first place. Lets just not create an uevent for it and lets not create a dev_t for it.  
> > 
> > Because if you don't it's a regression. It's not permissible to break
> > existing userspace.  
> 
> Well... it would be good to do the right thing, at least in the places
> where we can.
> 
> Yes, renumbering people's serials is bad, OTOH for new platforms it
> would be nice not to expose ttyS15 which can only return -EBUSY.

That would still be a regression. Not everyone even uses the kernel
bluetooth stack. It would only return EBUSY if you had done an "up" on it
via the direct bluetooth stack.

Alan