Re: [PATCH v2 2/4] dt-bindings: add bus number property

[Alexandre Belloni]

On 05/10/2021 18:22:12+0200, Arnd Bergmann wrote:
> On Tue, Oct 5, 2021 at 4:37 PM Paweł Anikiel <pan@xxxxxxxxxxxx> wrote:
> >
> > On SoCFPGA systems, it's desireable to have fixed numbering for
> > i2c busses, while being able to enable/disable them (e.g. have i2c1
> > be mapped to /dev/i2c-1, even though i2c0 is disabled). This can also
> > be achieved using devicetree aliases (see i2c_add_adapter). However,
> > having the driver be self-contained without relying on aliases is more
> > robust.
> >
> > Signed-off-by: Paweł Anikiel <pan@xxxxxxxxxxxx>
> 
> I don't see how adding a nonstandard property in one of the i2c bus
> drivers helps at all. How do you expect this to work when there are
> multiple i2c controllers in the system using different drivers? What
> should happen if both an alias and the busno property are set?
> 

What happens when two nodes have the same busno property because e.g.
one is in a dtsi and the other one is in a dts?


-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com