linux-kernel - Re: [PATCH 1/2] auxdisplay: HD44780 connected to I2C via PCF8574

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Date:   Wed, 6 Jan 2021 11:37:25 +0100
From:   Ralf Schlatterbeck <rsc@...tux.com>
To:     Geert Uytterhoeven <geert@...ux-m68k.org>
Cc:     linux-kernel <linux-kernel@...r.kernel.org>,
        Willy Tarreau <w@....eu>, Lars Poeschel <poeschel@...onage.de>,
        Linus Walleij <linus.walleij@...aro.org>,
        Miguel Ojeda <miguel.ojeda.sandonis@...il.com>
Subject: Re: [PATCH 1/2] auxdisplay: HD44780 connected to I2C via PCF8574

Miguel, Geert, thanks for the quick feedback.

On Wed, Jan 06, 2021 at 09:03:13AM +0100, Geert Uytterhoeven wrote:
> 
> Unless I'm missing some little detail, there should be no need for this
> driver: this wiring (and alternative wirings) can just be expressed in DT.
> Examples (using 74HC595 SPI GPIO expanders) can be found in my
> renesas-overlays branch:

Thanks for the examples.
I've tried this and it really works!
It feels somewhat slower (I'm using user-defined characters) but that
probably doesn't warrant its own driver.

So I'll contribute a documentation change that adds an example of how
to use the I2C-enabled version of the display, this may be non-obvious
to others. I'll start a new thread for this, stay tuned...

@Miguel: Thanks for your detailed feedback on coding style, I'll use
this next time ;-)

Ralf
-- 
Ralf Schlatterbeck                      Tel:   +43/2243/26465-16
Open Source Consulting                  www:   www.runtux.com
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