Re: [PATCH] dt-bindings: mtd: ti,gpmc-nand: Add missing 'rb-gpios'

[Roger Quadros <rogerq@kernel.org>]

Miquel,

On 09/12/2021 12:40, Miquel Raynal wrote:
> Hi Roger,
> 
> rogerq@kernel.org wrote on Thu, 9 Dec 2021 12:08:07 +0200:
> 
>> Hi Miquel,
>>
>> On 09/12/2021 11:42, Miquel Raynal wrote:
>>> Hi Rob,
>>>
>>> robh@kernel.org wrote on Mon,  6 Dec 2021 11:42:09 -0600:
>>>   
>>>> With 'unevaluatedProperties' support implemented, the TI GPMC example
>>>> has a warning:
>>>>
>>>> Documentation/devicetree/bindings/memory-controllers/ti,gpmc.example.dt.yaml: nand@0,0: Unevaluated properties are not allowed ('rb-gpios' was unexpected)
>>>>
>>>> Add the missing definition for 'rb-gpios'.  
>>>
>>> rb-gpios is already defined in nand-controller.yaml. I seems like the
>>> real problem is that this file does not refer to it. Can you update the
>>> fix?  
>>
>> I don't think we can refer to nand-controller.yaml right now as we are not
>> fully compatible with it yet. Please see examples below.
> 
> This is a *very* wrong way of defining a NAND setup. I will take the
> patch to silence the warning, but please convert this representation to

Thanks!

> the 'new' one. I believe on the driver side it should not be too
> complicated to support having a few of these properties moved to a NAND
> chip subnode and still support the below binding. Just be very clear
> that if the legacy bindings are used, only a single chip is supported.

I agree with you. It has been that way since ages. I will look at cleaning
it up whenever possible for me. I think we will have to support the old
bindings as well as the new one going forward as many legacy platforms
are using it.

cheers,
-roger

> 
>> ti,gpmc-nand example:
>>
>>       nand@0,0 {
>>         compatible = "ti,omap2-nand";
>>         reg = <0 0 4>;          /* device IO registers */
>>         interrupt-parent = <&gpmc>;
>>         interrupts = <0 IRQ_TYPE_NONE>, /* fifoevent */
>>                      <1 IRQ_TYPE_NONE>; /* termcount */
>>         ti,nand-xfer-type = "prefetch-dma";
>>         ti,nand-ecc-opt = "bch16";
>>         ti,elm-id = <&elm>;
>>         #address-cells = <1>;
>>         #size-cells = <1>;
>>
>>         /* NAND generic properties */
>>         nand-bus-width = <8>;
>>         rb-gpios = <&gpmc 0 GPIO_ACTIVE_HIGH>;  /* gpmc_wait0 */
>>
>>         /* GPMC properties*/
>>         gpmc,device-width = <1>;
>>
>>         partition@0 {
>>           label = "NAND.SPL";
>>           reg = <0x00000000 0x00040000>;
>>         };
>>         partition@1 {
>>           label = "NAND.SPL.backup1";
>>           reg = <0x00040000 0x00040000>;
>>         };
>>       };
>>
>>
>> nand-controller example:
>>
>>     nand-controller {
>>       #address-cells = <1>;
>>       #size-cells = <0>;
>>       cs-gpios = <0>, <&gpioA 1>; /* A single native CS is available */
>>
>>       /* controller specific properties */
>>
>>       nand@0 {
>>         reg = <0>; /* Native CS */
>>         nand-use-soft-ecc-engine;
>>         nand-ecc-algo = "bch";
>>
>>         /* controller specific properties */
>>       };
>>
>>       nand@1 {
>>         reg = <1>; /* GPIO CS */
>>       };
>>     };
>>
>>
>>>
>>> While at it you might also want to drop the rb-gpios property from
>>> ingenic,nand.yaml, which also defines it a second time.
>>>   
>>>> Cc: Miquel Raynal <miquel.raynal@bootlin.com>
>>>> Cc: Richard Weinberger <richard@nod.at>
>>>> Cc: Vignesh Raghavendra <vigneshr@ti.com>
>>>> Cc: Tony Lindgren <tony@atomide.com>
>>>> Cc: Roger Quadros <rogerq@kernel.org>
>>>> Cc: linux-mtd@lists.infradead.org
>>>> Signed-off-by: Rob Herring <robh@kernel.org>
>>>> ---
>>>>  Documentation/devicetree/bindings/mtd/ti,gpmc-nand.yaml | 5 +++++
>>>>  1 file changed, 5 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/mtd/ti,gpmc-nand.yaml b/Documentation/devicetree/bindings/mtd/ti,gpmc-nand.yaml
>>>> index beb26b9bcfb2..1c280f52baa0 100644
>>>> --- a/Documentation/devicetree/bindings/mtd/ti,gpmc-nand.yaml
>>>> +++ b/Documentation/devicetree/bindings/mtd/ti,gpmc-nand.yaml
>>>> @@ -53,6 +53,11 @@ properties:
>>>>      enum: [8, 16]
>>>>      default: 8
>>>>  
>>>> +  rb-gpios:
>>>> +    description:
>>>> +      GPIO connection to R/B signal from NAND chip
>>>> +    maxItems: 1
>>>> +
>>>>  patternProperties:
>>>>    "@[0-9a-f]+$":
>>>>      $ref: "/schemas/mtd/partitions/partition.yaml"  
>>>
>>> Thanks,
>>> Miquèl
>>>   
>>
>> cheers,
>> -roger
>>
> 
> Thanks,
> Miquèl
>