Re: [PATCH v3 2/3] dt-bindings: nand: Add fsl,elbc-fcm-nand

[Miquel Raynal <miquel.raynal@bootlin.com>]

On 08/03/2025 at 18:40:43 GMT, J. Neuschäfer <j.ne@posteo.net> wrote:

> Miquel, what do you think about Rob's suggestion below?
>
> On Mon, Mar 03, 2025 at 08:00:21AM -0600, Rob Herring wrote:
>> On Wed, Feb 26, 2025 at 12:45:17PM -0600, Rob Herring (Arm) wrote:
>> > 
>> > On Wed, 26 Feb 2025 18:01:41 +0100, J. Neuschäfer wrote:
>> > > Formalize the binding already supported by the fsl_elbc_nand.c driver
>> > > and used in several device trees in arch/powerpc/boot/dts/.
>> > > 
>> > > raw-nand-chip.yaml is referenced in order to accommodate situations in
>> > > which the ECC parameters settings are set in the device tree. One such
>> > > example is in arch/powerpc/boot/dts/turris1x.dts:
>> > > 
>> > > 	/* MT29F2G08ABAEAWP:E NAND */
>> > > 	nand@1,0 {
>> > > 		compatible = "fsl,p2020-fcm-nand", "fsl,elbc-fcm-nand";
>> > > 		reg = <0x1 0x0 0x00040000>;
>> > > 		nand-ecc-mode = "soft";
>> > > 		nand-ecc-algo = "bch";
>> > > 
>> > > 		partitions { ... };
>> > > 	};
>> > > 
>> > > Reviewed-by: Frank Li <Frank.Li@nxp.com>
>> > > Signed-off-by: J. Neuschäfer <j.ne@posteo.net>
>> > > ---
>> > > 
>> > > V3:
>> > > - remove unnecessary #address/size-cells from nand node in example
>> > > - add Frank Li's review tag
>> > > - add missing end of document marker (...)
>> > > - explain choice to reference raw-nand-chip.yaml
>> > > 
>> > > V2:
>> > > - split out from fsl,elbc binding patch
>> > > - constrain #address-cells and #size-cells
>> > > - add a general description
>> > > - use unevaluatedProperties=false instead of additionalProperties=false
>> > > - fix property order to comply with dts coding style
>> > > - include raw-nand-chip.yaml instead of nand-chip.yaml
>> > > ---
>> > >  .../devicetree/bindings/mtd/fsl,elbc-fcm-nand.yaml | 68 ++++++++++++++++++++++
>> > >  1 file changed, 68 insertions(+)
>> > > 
>> > 
>> > My bot found errors running 'make dt_binding_check' on your patch:
>> > 
>> > yamllint warnings/errors:
>> > 
>> > dtschema/dtc warnings/errors:
>> > /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/mtd/fsl,elbc-fcm-nand.example.dtb: nand@1,0: $nodename:0: 'nand@1,0' does not match '^nand@[a-f0-9]$'
>> > 	from schema $id: http://devicetree.org/schemas/mtd/fsl,elbc-fcm-nand.yaml#
>> 
>> Drop the unit address in raw-nand-chip.yaml. So: 
>> 
>> properties:
>>   $nodename:
>>     pattern: "^nand@"

I am not a big fan of lowering the constraint, but if our current schema
doesn't allow to express this need differently, we may need to do that.
I obviously trust Rob on this regard.

Thanks,
Miquèl