Re: [PATCH mmc-next v3 1/2] dt-bindings: mmc: add alias example

[Matthias Schiffer]

On Fri, 2020-08-28 at 16:24 -0600, Rob Herring wrote:
> On Tue, Aug 25, 2020 at 03:44:40PM +0200, Matthias Schiffer wrote:
> > As for I2C and SPI, it now is possible to reserve a fixed index for
> > mmc/mmcblk devices.
> > 
> > Signed-off-by: Matthias Schiffer <matthias.schiffer@xxxxxxxxxxxxxxx
> > >
> > ---
> > 
> > v3: new patch
> > 
> >  Documentation/devicetree/bindings/mmc/mmc-controller.yaml | 8
> > ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/mmc/mmc-
> > controller.yaml b/Documentation/devicetree/bindings/mmc/mmc-
> > controller.yaml
> > index b96da0c7f819..22ed4a36c65d 100644
> > --- a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
> > +++ b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
> > @@ -367,6 +367,14 @@ examples:
> >      };
> >  
> >    - |
> > +    /*
> > +     * Optionally define an alias to reserve a fixed index for the
> > +     * mmc and mmcblk devices
> > +     */
> > +    aliases {
> > +        mmc0 = &mmc3;
> > +    };
> 
> This will break if we improve schemas because this node is actually 
> /example-1/aliases.
> 
> So please drop. If you want, I'd really like to have a defined set
> (i.e. 
> a schema) of alias names. This would require deleting a bunch on
> some 
> platforms that just made up a bunch of them.

Ulf suggested that I add some kind of documentation about the new mmc
alias support to the binding docs.

As long as we don't have a proper schema for aliases, should I just add
an explanation to the toplevel description of
Documentation/devicetree/bindings/mmc/mmc-controller.yaml, or maybe a
comment?


> 
> > +
> >      mmc3: mmc@1c12000 {
> >          #address-cells = <1>;
> >          #size-cells = <0>;
> > -- 
> > 2.17.1
> >