[U-Boot] [PATCH] 7/12 Multiadapter/multibus I2C, drivers part 4

ksi at koi8.net ksi at koi8.net
Tue Feb 17 22:22:50 CET 2009


On Mon, 16 Feb 2009, Wolfgang Denk wrote:

> Dear ksi at koi8.net,
> 
> In message <Pine.LNX.4.64ksi.0902152224290.17769 at home-gw.koi8.net> you wrote:
> > 
> > > Yes, good point. But do we need more then one i2c adapter when running
> > > from flash? I see only one reason to use i2c when running from flash:
> > > accessing SPD EEprom ... and this "bus" could always be the first
> > > hw adapter. All other accesses to i2c should be moved to run when
> > > we are in ram.
> > 
> > You can have, e.g. TWO SPD EEPROMs on different busses. And please remember
> > that infamous "640K ought to be enough for anybody..."
> 
> This is a very unlikely hypothetical case. Based on such assumptions
> you can design any arbitrary complexity in any code.
> 
> For now, please lets assume that there is no such usage mode, and
> that we do not add complexity to support it.
> 
> 
> > I don't think there is a viable reason to object unless somebody came up
> > with something better.
> 
> Well, complex code  that  is  difficult  to  read  and  difficult  to
> understand is a very viable reason to object, me thinks.

The code is not all that complex. Most of the code is the same, there is
just a thin HAL over it. And it is _NOT_ for reading two SPDs on different
busses, it is for consistency and uniformity. Reading two SPDs is a free
bonus, there is no a single line of additional code for this.

---
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*  KSI at home    KOI8 Net  < >  The impossible we do immediately.  *
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