Re: [PATCH 3/7] pwm: dwc: add of/platform support

[Ben Dooks <ben.dooks@sifive.com>]

On 12/07/2022 23:17, Rob Herring wrote:
> On Tue, Jul 12, 2022 at 11:01:09AM +0100, Ben Dooks wrote:
>> The dwc pwm controller can be used in non-PCI systems, so allow
>> either platform or OF based probing.
>>
>> Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
>> ---
>>   .../devicetree/bindings/pwm/pwm-synposys.yaml | 40 ++++++++++++++
> 
> Use compatible string for filename.

ok, will fix.

>>   drivers/pwm/Kconfig                           |  5 +-
>>   drivers/pwm/pwm-dwc.c                         | 53 +++++++++++++++++++
>>   3 files changed, 96 insertions(+), 2 deletions(-)
>>   create mode 100644 Documentation/devicetree/bindings/pwm/pwm-synposys.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/pwm/pwm-synposys.yaml b/Documentation/devicetree/bindings/pwm/pwm-synposys.yaml
>> new file mode 100644
>> index 000000000000..38ac0da75272
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/pwm/pwm-synposys.yaml
>> @@ -0,0 +1,40 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +# Copyright (C) 2022 SiFive, Inc.
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/pwm/pwm-synposys.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Synopsys PWM controller
>> +
>> +maintainers:
>> +   - Ben Dooks <ben.dooks@sifive.com>
>> +
>> +properties:
>> +  "#pwm-cells":
>> +    description: |
>> +      See pwm.yaml in this directory for a description of the cells format.
> 
> pwm.yaml doesn't define how many cells. You need to. And you don't need
> generic descriptions.

  "#pwm-cells":
     const: 1

should be sufficient then?

>> +
>> +  clocks:
>> +    items:
>> +      - description: Interface bus clock
>> +      - description: PWM reference clock
>> +
>> +  clock-names:
>> +    items:
>> +      - const: bus
>> +      - const: timer
>> +
>> +  compatible:
> 
> Convention is compatible comes first in the list.

ok, fixed.


>> +    oneOf:
>> +      - items:
>> +        - const: snps,pwm
> 
> Don't need oneOf or items. Just 'const: snps,pwm'.

ok, fixed.


> That's pretty generic for a compatible. There's only 1 version of the IP
> or is the version discoverable?

This IP block doesn't seem to have evolved much since being included so
I don't think so at this point, most of the revision list is for the
internal options and cleanup.

I will go through and check if all the compile-time properties are deal
with, but that'll be adding more properiteis if they are needed.

>> +
>> +required:
>> +  - "#pwm-cells"
>> +  - compatible
>> +  - reg
>> +  - clocks
>> +  - clock-names
>> +
>> +additionalProperties: false