Re: [PATCH 1/4] i2c: introduce i2c-cbus driver

From: Felipe Balbi
Date: Fri Sep 14 2012 - 08:21:30 EST


On Fri, Sep 14, 2012 at 12:08:06PM +0200, Wolfram Sang wrote:
> On Mon, Sep 03, 2012 at 11:23:22PM +0300, Aaro Koskinen wrote:
> > Add i2c driver to enable access to devices behind CBUS on Nokia Internet
> > Tablets.
> >
> > The patch also adds CBUS I2C configuration for N8x0 which is one of the
> > users of this driver.
> >
> > Cc: linux-i2c@xxxxxxxxxxxxxxx
> > Acked-by: Felipe Balbi <balbi@xxxxxx>
> > Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>
> > Signed-off-by: Aaro Koskinen <aaro.koskinen@xxxxxx>
>
> OK, I found the short paragrahp about CBUS in the I2C spec, so I2C might
> be an appropriate place. Still, before deciding if it should rather be
> in the core directory, I still have a few questions.
>
> Also, does anybody know of a generic bit-banging implementation in the
> kernel which could be used here?

there is i2c-gpio, but it wouldn't help much for cbus, unless we change
it quite a lot. The generic i2c_algo_bit_data would have to be changed
to learn about a 3 wire bus. I guess the impact is much bigger than just
accepting this small, self-contained driver.

--
balbi

Attachment: signature.asc
Description: Digital signature