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Date:   Wed, 31 Aug 2022 16:12:36 +0200
From:   Davide Ciminaghi <ciminaghi@gnudd.com>
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Arnd Bergmann <arnd@arndb.de>,
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Subject: Re: [PATCH] gpio: Allow user to customise maximum number of GPIOs
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On Wed, Aug 31, 2022 at 03:32:25PM +0200, Linus Walleij wrote:
> On Tue, Aug 30, 2022 at 9:58 AM Davide Ciminaghi <ciminaghi@gnudd.com> wrote:
> 
> > the sta2x11 was a chip containing AMBA peripherals and a PCIe to AMBA bridge
> > (it is still in production as far as I know, but deprecated for new designs).
> > It would typically be installed on x86 machines, so you needed to build and
> > run AMBA drivers in an x86 environment. The original drivers we started from
> > had platform data, but then we were told to switch to DTS.
> 
> For the record I think that was bad advice, I hope it wasn't me.
> But the world was different back then I suppose.
> Adding DTS to x86 which is inherently ACPI is not a good idea.
> Especially if you look at how SBSA ACPI UARTS were done
> in drivers/tty/serial/amba-pl011.c.
>
now that I think of it, ACPI was also listed as a possible choice, but the
problem was that we didn't know much about ACPI, and took the DTS way.
So there was no bad advice, just fear of the unknown :-)

Thanks
Davide