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From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: Mon, 4 Mar 2024 10:57:18 +0100
Message-ID: <CAMuHMdXjqVQeQF6TFr1nQmUCLrEbY1gq5OdCcz6T60W33QO2-Q@mail.gmail.com>
Subject: Re: [PATCH v3 4/4] ARM: dts: marvell: Indicate USB activity on x530
To: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Andy Shevchenko <andy@kernel.org>, Chris Packham <chris.packham@alliedtelesis.co.nz>, 
	robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, 
	andrew@lunn.ch, gregory.clement@bootlin.com, sebastian.hesselbarth@gmail.com, 
	pavel@ucw.cz, lee@kernel.org, linux-leds@vger.kernel.org, 
	linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, 
	linux-arm-kernel@lists.infradead.org
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Hi Andy,

On Sun, Mar 3, 2024 at 9:43=E2=80=AFPM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> On Sun, Mar 3, 2024 at 11:48=E2=80=AFAM Geert Uytterhoeven <geert@linux-m=
68k.org> wrote:
> > On Fri, Mar 1, 2024 at 7:24=E2=80=AFPM Andy Shevchenko <andy@kernel.org=
> wrote:
> > > The problem here as I see it is the future decision on how DP should
> > > behave like.  If you put this into DT, we will to support this to the=
 end
> > > of the platform.
> >
> > As there exist 7-seg displays (and wirings) with and without DP,
> > the 7-seg driver and DT bindings should handle both cases.  How to
> > wire/use the DP LED is up to the hardware designer / DTS writer.
>
> Right. But my personal statistics for now is: 100% has DP (out of
> about a dozen of different chip + LED combinations). What's yours?

It's indeed hard to find contemporary 7-segment LED assemblies that
lack the DP.  But they do exist[1].  There's also no guarantee that the
DP is wired.
And don't forget custom or home-built assemblies using discrete LEDs,
especially for huge displays (e.g. using one LED-strip per segment).
So IMHO it would be a bad idea to make the DP mandatory.

[1] https://www.alibaba.com/product-detail/CC-CA-188-led-display-0_60626228=
913.html

Gr{oetje,eeting}s,

                        Geert

--=20
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k=
org

In personal conversations with technical people, I call myself a hacker. Bu=
t
when I'm talking to journalists I just say "programmer" or something like t=
hat.
                                -- Linus Torvalds