Re: [RFC] Rework of i2c-mpc.c - Freescale i2c driver

["Grant Likely" <grant.likely@secretlab.ca>]

On 11/6/07, Grant Likely <grant.likely@secretlab.ca> wrote:
> On 11/6/07, Jean Delvare <khali@linux-fr.org> wrote:
> > Hi Scott,
> >
> > On Tue, 06 Nov 2007 11:36:23 -0600, Scott Wood wrote:
> > > Jean Delvare wrote:
> > > >>>> We might as well just use i2c_new_device() instead of messing around
> > > >>>> with bus numbers.  Note that this is technically no longer platform
> > > >>>> code, so it's harder to justify claiming the static numberspace.
> > > >>> I was allowing control of the bus number with "cell-index" and
> > > >>> i2c_add_numbered_adapter().
> > > >>> Should I get rid of this and switch to i2c_add_adapter()?
> > > >> Yes.
> > > >
> > > > No! If you don't call i2c_add_numbered_adapter() then new-style i2c
> > > > clients will never work on your i2c adapter.
> > >
> > > I thought that was what i2c_new_device() was for?
> >
> > Sorry, I've not been completely clear. Yes, you can use
> > i2c_new_device() on an adapter that has been added with
> > i2c_add_adapter(). However, this requires that you have a reference to
> > that i2c_adapter, which is usually not the case with system-wide I2C
> > buses. Embedded platforms would rather use i2c_add_numbered_adapter(),
> > give a list of chips to i2c_register_board_info() and let i2c-core
> > instantiate them. i2c_new_device was primarily meant for multimedia
> > adapters.
>
> *Some* embedded platforms would rather use i2c_add_numbered_adapter().  :-)
>
> On powerpc, and other platforms which have a device tree, we don't

Specifically; an OF style device tree.  :-)

g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
grant.likely@secretlab.ca
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