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Date:   Wed, 22 Jun 2022 17:20:01 +0300
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Andrew Lunn <andrew@lunn.ch>
Cc:     Marcin Wojtas <mw@semihalf.com>,
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        Vladimir Oltean <olteanv@gmail.com>,
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Subject: Re: [net-next: PATCH 09/12] Documentation: ACPI: DSD: introduce DSA
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On Wed, Jun 22, 2022 at 01:22:15PM +0200, Andrew Lunn wrote:
> > > It's not device on MDIO bus, but the MDIO controller's register itself
> > > (this _CSR belongs to the parent, subnodes do not refer to it in any
> > > way). The child device requires only _ADR (or whatever else is needed
> > > for the case the DSA device is attached to SPI/I2C controllers).
> > 
> > More and more the idea of standardizing the MDIOSerialBus() resource looks
> > plausible. The _ADR() usage is a bit grey area in ACPI specification. Maybe
> > someone can also make it descriptive, so Microsoft and others won't utilize
> > _ADR() in any level of weirdness.
> 
> I don't know if it makes any difference, but there are two protocols
> spoken over MDIO, c22 and c45, specified in clause 22 and clause 45 of
> the 802.3 specification. In some conditions, you need to specify which
> protocol to speak to a device at a particular address. In DT we
> indicate this with the compatible string, when maybe it should really
> be considered as an extension of the address.
> 
> If somebody does produce a draft for MDIOSerialBus() i'm happy to
> review it.

I also can review it. Marcin, would it be hard for you to prepare a formal
proposal for ACPI specification?

-- 
With Best Regards,
Andy Shevchenko