Re: [[PATCH v2] 1/9] dt-bindings: pwm: Document Synopsys DesignWare snps,pwm
From: Krzysztof Kozlowski
Date: Tue Jul 26 2022 - 07:05:40 EST
On 26/07/2022 12:12, Ben Dooks wrote:
> On 26/07/2022 11:05, Krzysztof Kozlowski wrote:
>> On 25/07/2022 23:21, Ben Dooks wrote:
>>> Add documentation for the bindings for Synopsys' DesignWare PWM block
>>> as we will be adding DT/platform support to the Linux driver soon.
>>>
>>> Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxx>
>>> --
>>
>> This is not proper delimiter and causes the changelog to end up in commit.
>>
>> Correct also wrong formatting of subject PATCH.
>
> I realised that once sent and forgot the cover letter.
> Maybe I'll try some more post covid recovery.
>
>>> v2:
>>> - fix #pwm-cells to be 3
>>> - fix indentation and ordering issues
>>> ---
>>> .../devicetree/bindings/pwm/snps,pwm.yaml | 40 +++++++++++++++++++
>>> 1 file changed, 40 insertions(+)
>>> create mode 100644 Documentation/devicetree/bindings/pwm/snps,pwm.yaml
>>>
>>> diff --git a/Documentation/devicetree/bindings/pwm/snps,pwm.yaml b/Documentation/devicetree/bindings/pwm/snps,pwm.yaml
>>> new file mode 100644
>>> index 000000000000..594085e5e26f
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/pwm/snps,pwm.yaml
>>> @@ -0,0 +1,40 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>> +# Copyright (C) 2022 SiFive, Inc.
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/pwm/snps,pwm.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: Synopsys PWM controller
>>> +
>>> +maintainers:
>>> + - Ben Dooks <ben.dooks@xxxxxxxxxx>
>>> +
>>> +allOf:
>>> + - $ref: pwm.yaml#
>>> +
>>> +properties:
>>> + compatible:
>>> + const: snps,pwm
>>
>> This is very generic compatible. I doubt that you cover here all
>> Synopsys PWM designs, past and future. You need a specific compatible.
>
> From what I can get from the documentation (2.13a) there hasn't been
> a huge external interface change and what has been added is all part
> of synthesis time options.
But you have some specific version, right? Usually these blocks are
versioned, so you must include it. I would even argue that such generic
compatible should not be used as fallback at all, because it is simply
to generic (PWM is not some model name but common acronym),
Best regards,
Krzysztof