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Date:   Mon, 29 May 2023 17:07:02 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Chris Packham <Chris.Packham@alliedtelesis.co.nz>,
        Andy Shevchenko <andy.shevchenko@gmail.com>,
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Subject: Re: [PATCH] gpiolib: Avoid side effects in gpio_is_visible()
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On Mon, May 29, 2023 at 11:19:02AM +0200, Linus Walleij wrote:
> On Wed, May 17, 2023 at 11:30 PM Chris Packham
> <Chris.Packham@alliedtelesis.co.nz> wrote:
> 
> > > Why does the MCU have no in-kernel driver?
> >
> > There isn't any PoE PSE infrastructure in the kernel. I'm not really
> > sure what it'd look like either as the hardware designs are all highly
> > customized and often have very specialized requirements. Even the vendor
> > reference boards tend to use the i2c userspace interface and punt
> > everything to a specialist application.
> >
> > Of course if anyone is thinking about adding PoE PSE support in-kernel
> > I'd be very keen to be involved.

There is net/ethtool/pse-pd.c.

      Andrew