[RFC] I2C: fsl-i2c: make device probing configurable via FDT

Jon Smirl jonsmirl at gmail.com
Thu Jul 17 00:11:22 EST 2008


On 7/16/08, Wolfgang Grandegger <wg at grandegger.com> wrote:
> Jon Smirl wrote:
>
> > On 7/16/08, Wolfgang Grandegger <wg at grandegger.com> wrote:
> >
> > > Currently, the I2C buses are probed for HWMON I2C devices, which might
> > >  not be acceptable in same cases. This patch makes device probing
> > >  configurable through the property "probe" of the FDT I2C device node:
> > >
> >
> > All this patch seems to be doing is removing class I2C_CLASS_HWMON via
> > a device tree flag, PROBE.
> >
>
>  Yep.
>
>
> > Why do you need to do this? The OF conversion patch that is working
> > its way through the system lets you put the address of the device into
> > the device tree node. Probing shouldn't be necessary at all.
> >
>
>  Currently I2C_CLASS_HWMON is used for all I2C adapters and therefore
> probing is done even with a proper I2C node defined in the DTS file. That's
> what the patch is fixing leaving the possibility to (re-)enable legacy
> probing.

Shouldn't we just remove I2C_CLASS_HWMON since everything can now be
explicitly described in the device tree? What is an example of a case
where we still need to probe?

>
>  For some more details you may want to have a look to Jean's mail on that
> subject:
> http://ozlabs.org/pipermail/linuxppc-dev/2008-July/060012.html.
>
>  Wolfgang.
>
>
>


-- 
Jon Smirl
jonsmirl at gmail.com



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