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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Nathan Whitehorn <nwhitehorn@freebsd.org>
References: <4929877B.6060307@freebsd.org>
Date: Sun, 23 Nov 2008 19:18:25 +0100
In-Reply-To: <4929877B.6060307@freebsd.org> (Nathan Whitehorn's message of
	"Sun, 23 Nov 2008 10:40:27 -0600")
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Cc: freebsd-arch@freebsd.org
Subject: Re: Enumerable I2C busses
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Nathan Whitehorn <nwhitehorn@freebsd.org> writes:
> The current I2C bus mechanism does not support the bus adding its own
> children [...]

That's because the I2C protocol does not support device enumeration or
identification.  You have to know in advance what kind of devices are
attached and at what address.  Even worse, it is not uncommon for
similar but not entirely compatible devices to use the same I2C address
(for instance, every I2C-capable RTC chip uses the same address, even
though they have different feature sets)

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no