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Date: Thu, 31 Jul 2008 15:37:07 -0500
From: Timur Tabi <timur@freescale.com>
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To: Grant Likely <grant.likely@secretlab.ca>
Subject: Re: [PATCH] powerpc: i2c-mpc: make speed registers configurable via
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Cc: Scott Wood <scottwood@freescale.com>, Linuxppc-dev@ozlabs.org,
	Linux I2C <i2c@lm-sensors.org>
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Grant Likely wrote:

> How is the divider controlled?  Is it a fixed property of the SoC? 

Yes.  The divider is either 1, 2, or 3, and the only way to know which one it is
is to look up the specific SOC model number.  And depending on the SOC model,
there may also be a register that needs to be looked up.

> a
> shared register setting? or a register setting within the i2c device?

The I2C device itself has no idea what the divider is.  It only sees the result
of the divider.

-- 
Timur Tabi
Linux kernel developer at Freescale