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Date: Mon, 9 Sep 2019 09:23:31 +0200
From: Sascha Hauer <s.hauer@pengutronix.de>
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Subject: Re: [PATCH] gpio: add driver for SN74273 output expander
To: Ahmad Fatoum <a.fatoum@pengutronix.de>
Cc: barebox@lists.infradead.org

On Fri, Sep 06, 2019 at 04:01:27PM +0200, Ahmad Fatoum wrote:
> The SN74273 is an octal D-Type Flip-Flop. When used as an output expander,
> N existing output signals can be turned into (N-8)*8 outputs using
> N-8 chips. Add driver to facilitate this.

The reason I haven't mainlined this driver when writing it was that
Linux also has a driver for the 74273, but in a completely different
setup. In the Linux driver the 74273 is assumed to have its inputs on
the data bus together with a separate address decoder.
The chip in this driver here instead is connected via GPIO pins. For
Using flipflops as GPIO expanders there a myriads of different ways to
implement, so I have my doubts how useful it is to even try to put them
in a generic driver.

Sascha

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