Re: [PATCH 02/10] dt-bindings: net: can: grcan: Convert GRCAN CAN controllers binding from txt to YAML

[Arun Muthusamy]

Hi Krzysztof,

Thank you for your thorough review. I’d like to clarify a few points 
regarding the DT binding and get your guidance.

On 11/18/25 12:01, Krzysztof Kozlowski wrote:
> On 18/11/2025 10:21, Arun Muthusamy wrote:
> > +      Fallback on node name matching for systems that don't provide compatible.
> > +    enum:
> > +      - GAISLER_GRCAN
> > +      - 01_03d
> > +      - GAISLER_GRHCAN
> > +      - "01_034"
> This does not really work. Are you really defining here "name" property?

The driver supports two of the platforms which are LEON and NOEL 
platforms. PROM-based *LEON* systems identify uses the "node name" 
property, while DTS based *NOEL* systems use proper "|compatible"|strings. On LEON (SPARC32), AMBA Plug & Play information creates the DT 
properties, and drivers historically match devices based on node names.
To reflect this, I updated the $nodename pattern to support LEON-style 
node names: properties:
  $nodename:
    pattern: "^(GAISLER_GRCAN|01_03d|GAISLER_GRHCAN|01_034)$" I’d 
appreciate any suggestions on the preferred way to describe this node 
name for PROM-based LEON.

> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    maxItems: 1
> > +
> > +  freq:
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    description: |
> > +      Frequency of the external oscillator clock in Hz (the frequency of the
> > +      amba bus in the ordinary case).
> > +      This property should be used by systems that utilize the common clock
> > +      framework is not supported.
> Missing systemid. Your commit msg must explain any changes done to the
> binding during conversion.

The driver now reads systemid directly from /ambapp0, so the property no 
longer needs to be defined in the DTS. The previous documentation was 
outdated and should have been updated after commit:
1e93ed26acf0 ("can: grcan: grcan_probe(): fix broken system id check for 
errata workaround needs").

> > +  - reg
> > +  - interrupts
> Where is freq? It was required in the old binding. Again, you need to
> explain the changes.

LEON: relies on the freq property
NOEL: uses a standard clocks binding
Because of this dual approach, the freq property is no longer required 
in the DTS binding itself as theAMBA Plug & Play creates the DT properties.


Thanks,

--
BR,

Arun Muthusamy
Software Engineer
Frontgrade Gaisler
T : +46 (0) 700 558 528
arun.muthusamy@xxxxxxxxxxx

Frontgrade Gaisler AB, Kungsgatan 12, SE-411 19 GÖTEBORG, Sweden.
+46 (0) 31 775 8650,www.gaisler.com <http://www.gaisler.com/>