Re: [PATCH v2 2/9] dt-bindings: spi: zynqmp-qspi: Add example dual upper/lower bus

[Sean Anderson <sean.anderson@linux.dev>]

On 6/18/25 14:27, David Lechner wrote:
> On 6/16/25 5:00 PM, Sean Anderson wrote:
>> Add an example of the spi-buses property showcasing how to have devices
>> on both the upper and lower buses.
>> 
>> Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
>> ---
>> 
>> Changes in v2:
>> - New
>> 
>>  .../bindings/spi/spi-zynqmp-qspi.yaml         | 22 ++++++++++++++++++-
>>  1 file changed, 21 insertions(+), 1 deletion(-)
>> 
>> diff --git a/Documentation/devicetree/bindings/spi/spi-zynqmp-qspi.yaml b/Documentation/devicetree/bindings/spi/spi-zynqmp-qspi.yaml
>> index 02cf1314367b..c6a57fbb9dcf 100644
>> --- a/Documentation/devicetree/bindings/spi/spi-zynqmp-qspi.yaml
>> +++ b/Documentation/devicetree/bindings/spi/spi-zynqmp-qspi.yaml
> 
> 
> In addition to changing the example, we could also extend the
> spi-buses property for this controller since we know this controller
> has 2 buses.
> 
>   properties:
>     ...
> 

OK, but this property is for the slaves not the master. I'm not sure what the right incantation is.

>     spi-buses:
>       description: 0 is the "lower" bus, 1 is the "upper" bus
>       maxItems: 2
>       items:
>         enum: [0, 1]
> 
> Not sure what to do about the default though since as discussed elsewhere,
> this controller needs the default bus number to be the CS number for
> backwards compatibility rather than `default: [0]` as is specified in the
> previous patch.
> 
> I suppose we could leave default out of the generic binding and leave it
> up to each individual controller to decide how to handle that.
> 
>> @@ -69,7 +69,7 @@ examples:
>>        #address-cells = <2>;
>>        #size-cells = <2>;
>>  
>> -      qspi: spi@ff0f0000 {
>> +      qspi: spi-controller@ff0f0000 {
> 
> It seems more common to have spi@ rather than spi-controller@.
> Is there a push to change this in general?

iirc I got a warning when running dt_binding_check. I can re-test this...

--Sean