Re: [PATCH v2] ARM: dts: am335x-bone-common: Add i2c2 definition

[Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>]

* Robert Nelson <robertcnelson-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> [140512 13:27]:
> >> >
> >> > If these pins are not used for i2c2 on some capes, this device
> >> > should be set to status = "disabled" state by default. Then
> >> > u-boot could re-enable it on the boards that have i2c2 in use.
> >>
> >> To-date, this is the i2c bus that all capes have placed an at24 eeprom
> >> for cape identification.
> >
> > And how many capes actually implement the eeprom cape identification
> > out of the available capes? :)
> 
> Not including one off designs in someone's lab. We will never have an
> accurate number. ;)
> 
> So far; just the ones that want their "cape" detected in the default
> image currently being shipped by CircuitCo. Otherwise the few that
> I've seen without an eeprom, usually follow this default pinmux.
> 
> http://elinux.org/CircuitCo:Basic_Proto_Cape
> 
> Which includes that i2c bus enabled.

OK thanks for the info.
 
> Either case if fine with me.  As who knows when the dtc "overlay" will
> every truly make it mainline, as the capemgr was the only real kernel
> user of the i2c/at24 eeprom information.

Sounds like we should keep it disabled though so u-boot can be used
to toggle it while waiting for the capemgr. That's because the board
has a header for pins, so it's not exactly limited to just the capes.

Anybody working on enabling/disabling cape dtb configurations in u-boot?

Regards,

Tony
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