[i2c] [PATCH] powerpc: i2c-mpc: make speed registers configurable via FDT

[Trent Piepho]

On Thu, 31 Jul 2008, Grant Likely wrote:
> >>  I'm a bit confused. The frequency of the I2C source clock and the real I2C
> >> clock frequency are two different things. The first one is common for all
> >> I2C devices, the second can be different. What properties would you like to
> >> use for defining both?
>
> How is the divider controlled?  Is it a fixed property of the SoC?

Usually.

> a shared register setting?

Sometimes.

> or a register setting within the i2c device?

Never.


Thinking of it as the CCB divided by 1, 2, 3 isn't really right.  It's just
some internal clock that I2C was connected to.  Sometimes it's the clock
for the ethernet block of the SoC.  Sometimes it comes from some other
block.