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Date: Mon, 22 Aug 2016 22:32:23 +0100
From: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
To: Marcel Holtmann <marcel@holtmann.org>
Cc: Rob Herring <robh@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
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Subject: Re: [RFC PATCH 0/3] UART slave device bus
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> 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.

> Internally the setup stage does a hciconfig hci0 up and it is already abstracted out that way. So there has been a lot of work in the Bluetooth subsystem to allow for this. That part is really solved.

So you'd create a kernel side tty struct and bind it to the tty_port on
hci0 up and drop it on hci0 down ?

Alan